Mostly none, but if you belong to something that would be a good reason to believe in it or support it.

My hobby encompasses a large international community and the largest number of my favorite friends and acquaintances were developed through that, but I also have active friendships with people I've known since I started elementary school. I am fortunate in the tribes I can claim.

I belong to a writing salon that's been a huge source of support for me for over 20 years. We meet once a month, and all have different backgrounds. But many of us are largely in touch outside of the group, too. Being connected with them has been life-changing for me.

I was also for some time part of an interfaith community. That was very interesting as I got to know and understand different takes on spirituality. Even non-believers were accepted.

Extended family. Neighbors.
Hobby groups. Supporting organizations such as "At Risk" young mens mentoring. Alumni groups.

As a person who was raised in the church, over the years many of my friends were thru the church, now I don't really know where to meet people

The so called face-to-face social or religious communities often provide, anger, guilt, disappointment and sometimes death too. Just look at the 600 + years of Spanish Inquisition. If one likes one can start ones own ongoing community that has meaning. Just get some like minded people together, to meet for friendship and mutual interests and those interests can just be anything.

Unfortunately, religion still is a big part of many people's lives. The same way there are more groups that religious based for that purpose, these days there will be already quite a few that have nothing to do with religion. Hopefully I'll be back in doing tango in January, which is also a good social network although I want to be back for the exercise and because it will help me with my mental health, I'm quite anti-social nowadays. So, it's a question of finding a group that suits you.

Back when the Occupy Movement was a thing, I went to a few meetings of the local chapter and met some wonderful folks who have become my IRL social base.

IamSure we could write down an encyclopedia here, but I'll stick to the simple response: NONE

I’ve been to humanist gatherings and they are super serious people and the group I went to just seemed to bicker a lot. Not much fun.

Having never been religious I would not know, but your friend could be correct.

I am a loner, yet I do lot with our local community centre, 250 plus volunteers, no Gov funding and we provide so much of the support our region needs. I act out a part when I am there, but when I am away from the centre, I am my own person, totally invisible around here. Some of our volunteers are older, many of them are religous, the organisation is not at all religous. We have no political affiliation and generally hold religion and politics in contemp. That said, the people I work with are great, we form small teams of people we get on with and just do what needs to be done. More than enough social interaction, maybe too much some times, I have never come across a church that does as much for the needy in a community as this group does.

The humanist society of greater phoenix.

We have a facility, regular speakers and other activities.

I host a monthly discussion group there.

The goal is to be that secular community alternative.

Send him to his website. [atheist-community.org]

My 'in-person community' consists of my good, decent and trusted friends, my neighbors ( barring a few that is), some of the counter staff at local corner shops and the many people I've and talk to regularly when I take the bus every fortnight.
I need no Church Congregation to create one their false communities for me, I have made my own and it works wonderfully I might add.

Accidents of coincidence don't necessarily deserve reinforcement. Just because something predominates does not mean it ought to. That people can be civil to each other despite their differences in philosophy is a better way to judge human interaction.

I'm nerdy. People who are also nerdy make for great like-minded "community members," in theory, but not everyone needs such things for self-esteem. I need a community of secularists, for example, like I need a hole in my sock. This is just a fun way to kill time.

So I live in PBG - anybody play euchre? Used to have 4 of us guys do dinner (at home) and play euchre once a week

None. Except I text a friend and my sister-in-law...THIS is as close as I get to 'community.'

I’ve said elsewhere, I have been, at times in my life, involved in Rotary and I really enjoy that generally. Choirs can be ok if it’s the right one. I like my workplace too. Some pubs, but I’m not a big fan of alcohol so that’s taken a bit of a dive

Bars

Sorry. I'm a natural introvert. Solitude is my bliss.

However, regarding the notion that religion provides opportunity for social interaction, I feel I should point out: 1) If you hold mandatory meetings every Sunday for any reason, THAT will provide an equal opportunity for social interaction.
Like your job (if you're lucky).A consistent social environment in which the community works together towards a common goal.

2. I think religion practices a sham of community. A placebo.
   A real community comes together for a common purpose; not just to all sit together in the same building. If that was true I'd have a "community" with the people I see regularly on the train.

What about the social structure of the various Indian tribes (Native American), African tribes, Amazon Basin tribes, etc.? As to "What communities...ongoing meaning for you...", actually I am an Asperger's and as an older person, I have morphed into a recluse, so none.

You've got to be kidding! The argument that there's nothing like, ole time religion, is not taking into consideration the fact that every historical culture has it's, ole time religion.
Having said that; as Ron L. Hubbard said, "If you want to be rich, start a religion." I'm in the wrong racket!

I have increasingly come to the conclusion that we need far less than we think we do.

It took my wife the 7 years since we moved to our current location to find a friend that she really "clicks" with in an organic and uncomplicated way but once she did she found it was all she needed, given that her friend proposes more than enough things for them to do together. As a bonus, I like the woman's husband and it's mutual. So now we have occasional couples activities too.

I play no-stakes 500 Rummy with some other old guys on Saturday mornings. It's easy to succeed at such a modest goal.

A lot of one's sense of community and belonging comes from letting all your relationships be as they are without striving to make them something they are not. As such, most relationships are limited, but over time, you stumble on less limited ones. From this, you cobble together what you need.

Now of course my wife and I are introverts and so not only can, but need to, get by on less. Less is more for us. If you want to socialize frequently with a lot of people, then I agree with your friend that it's hard to beat (many, not all) churches for that. The nearest social resource of that scope is probably fraternal organizations, but those tend to be less family-friendly. After that, it comes down to professional and charitable involvements.

Sadly, neighborhoods aren't much help anymore. I live in a newer development and all the houses on our street have old-fashioned front porches and the homes are close together. Absolutely no one uses their front porch. I've sat on mine a couple of times and just feel exposed and alienated. From what the old timers used to tell me, in a pre-mass media era people used to go for evening strolls and visit with their neighbors along the way, who would be out in their yard or on their porch; their kids used to play at each other's houses, etc. Today I don't know the name of most of my neighbors. Their connections are all through work for the most part. The young and old don't interact. Everyone is jacked into their earbuds when they take a walk. Kids stay indoors playing video games. Different world.

Many comments below are correct. No one institution offers the same experience. Religion would not serve me at all. I have academic communities.