Mitch is of course, correct.
I urge you to use this website as a rules resource.
If you look at the pale green strip up top, you'll see a heading, "Billiard Rules." Go down the list to 8-ball and check it out. Almost all games have fundamental "rules," in addition to those rules specifically aimed at a particular game.
Check those out as well. I think they're called "general rules."
Also be aware that bar tables and rules almost always focus on 8-ball. Those of us who prefer home - or pool hall tables, typically, do NOT play 8-ball. We play 9-ball, Straight Pool (14.1), one pocket, 10-ball, Rotation (Chicago) and other forms of billiards.
Regardless of the game played, pool is a remarkably easy game to play, yet incredibly difficult to play well - or master.
Handicap systems level the playing field, just like golf.
Keep the questions coming!