The internet is your friend for learning your rifle. YouTube has a surprising number of rifle training videos. Here's the cycle of operation for the M-16:
When I was issued an M-16, we memorized facts about the rifle, it's functions, ammo, range, etc. We lived with the rifle, carried it, practiced disassembly and assembly. We were taught this information by people had both the means and the will to ensure that we were paying close attention. We were trained to shoot it effectively. The last time I held an M-16 was 1983.
When I had the opportunity (and time and money) to join a club that had ranges and competitions suitable for a rifle like that, it was 2002. I bought an AR-15, a model designed for shooting service rifle competition. The day I brought it home I put it on the bench and without a pause, I field stripped it for an initial cleaning and inspection. The memory was right there. I do not know any other rifle design as well as that one.
It might be your bolt action hunting rifle, worn from many years of deer hunting. It might be a new .22, bought for squirrels and tin cans. It doesn't matter what it is. If you are going to be effective and safe with that rifle, you need to know the same sorts of things about your rifle's design and the particular rifle you purchased.
There's a corollary to this.