Start from here :
Vedic Hinduism was simple, they worshipped everything that scared them or impressed them, to be precise natural powers like air, light, fire, rain, forests…
Some historians claim that though Hindus worshipped many powers but in fact they believed in a single God (just like me).
There were no priests, no complex/expensive rituals to follow to please or appease Gods, simple offerings like Ghrita (Indian butter I guess) and honey was enough, they were offered to the fire, the carrier of homage/offerings to Gods and that was it!
Then came the Brahmanya yuga- when Brahmins convinced others that they were the big cheese and they were indispensable part of every single ritual, Gods accepted prayers only when Brahmins performed complex rituals and chanted hymns. This part is still followed not that viciously but quite seriously, and I will have to sheepishly admit that if I ever start performing any puja on my own (which is in my bucket list after hitting jackpot) I will absolutely go for an actual Brahmin, who knows puja, not anyone who is born of a Brahmin or worse, claims that he is a Brahmin. But that is because I respect Hinduism not because I think Brahmins are necessary for reaching God. I don’t need any middle man to communicate with God, She is always listening to me!