This is a Game?
People have enjoyed tabletop Role-Playing games (TTRPGs) for half a century, yet most still explain what RPGs are at the start. As a nod to tradition, it's a set of rules for representing a character as the "role" you'll be playing, and fairly deciding whether things they try to do will succeed.
You probably already knew that, or would figure it out pretty quickly. You're not here for me to waste your time, so let's get to the point - how do we do it?
The Short Version
Grab some dice - any common dice will do. When your character tries something, figure out how good they are by adding up your bonuses. Roll that many dice and count the odd numbers. The Game Moderator, the person "running" the game, will total up things working against you and roll as well. If you roll better than they do you succeed by the difference.
Everything in the game works this way. If you punch a drunk in the bar, how much better you roll determines how hard you hit him. If he rolls better, he blocks and punches you!
The Rest of the Book
The system is simple and standard, but "add up your bonuses" is vague. What about damage? Initiative? Extra effort? Multiple attackers?
How do I build a barbarian? A wizard?
What if I want to play a werewolf?
Well, that's in the character book, but...
"The devil's in the details."
No reason to be sketchy.
Let's see what it looks like in action.