To assign credit or blame to/for events that could not yet be explained by science that was commonly understood. Or that people choose to be willfully ignorant of.

Why is the sky blue? God made it that way.
Why? God works in mysterious ways

And then, of course, power and control.

Who knows? Religion came to be from an animal on this planet called a human being. Just knowing that gives me plenty reason to believe it's originality was self centered.

I sincerely think that, IF one were to search back into the deepest recesses of the 'evolution' of religions one would find that it all stemmed from a tribal member/s realising that instead of putting him/her/themselves in the way of constant and ever present danger/s whilst assisting his/her fellows to hunt for game as food, they formulated an idea of possessing the ability/s to converse with the ' Spirit World' thus being ' able' to ' receive' messages from the 'other side' as to where and which game animals, etc, would be and the easiest to kill, etc.
Thus assuring them of the devotion and reverence of their fellow tribe members, the tastiest piece of the catch as by way of being an OFFERING to both the spirits and them for their intervention, a status among their fellows that assured that they would live a safe and well fed, contented life, etc, etc., and this idea has continued on through the millenia to be what see around us to this day, i.e. nothing more than the earliest form of a SCAM perpetrated by some, or a few, indolent, unscrupulous, self-serving prehistoric Hunter-Gather/s who saw the opportunity and grabbed it with both hands.

Neo-natal parent worship instinct?

As far as I can see ...to create war and division .

If you wish to make up your own gobbildygook and even use it as a method to live by, by all means do so. For others who are wise to the usage of religion your chances of convincing them will be minimal ?

'The opium of the people"

There are two different questions here.

1. what was the purpose of the “founder” of the religion.
2. what are the purposes of the owners of the religion
   Then we might ask why do people chose to believe.

What you describe is called philosophy.

Religion is merely supernatural philosophy.

I think religions are primarily the expression of the fight or flight instinct. At some point our ancestors' brains got big enough to grasp the concept of the future and that we will all eventually die. The instinct would have none of that so people came up with various ways to convince themselves that they will not die after they die. Obviously, that is not the only reason for religions but I think it is the main one. I read somewhere that out of the several thousand of religious beliefs only a few don't promise surviving death in one way or another. Other readons are the daddy in the sky that watches over you, the need for being to know what is right and what is wrong, the explanation of the unknown, ect.

When you cut through all the high brow justifications, about fear of death, making us feel part of something, control of people, populations, disease, and all the rest, I've come to think that religion at heart is a business. The customers are the gullible believers. The product is an intangible load of nonsense that can never be proved or disproved. Look at any sizeable religion and what do you find? Money and wealth. It's a fraudulent business that takes the money but never has to worry about unhappy customers because no one ever comes back from the dead to say they were sold a crock of crap. If prostitution is the world's oldest business, then religion runs a close second. In my older years I've stopped thinking of religion existing for all kinds of fancy psychological and philosophical reasons, and come to realize that's nothing more than legal fraud, with profit as its purpose.

To provide a simple explanation for how, why and when.

Answer = So you don't feel small!

It's sauve for the original authors.