"I have no idea what "blocking" is."
Blocking is the movement of actors on the stage and their positions on the stage. For example, if an actor enters through a door and crosses over to a sofa and sits down, that actor has been blocked to cross to the sofa and sit. For every show, the stage manager draws a diagram of all the positions of the actors on the stage and draws diagrams of all their movements while on the stage.
"and also, are all actors (ensemble included) members of the equity? and um..what exactly is the equity? I always assumed it's the union group of Broadway actors."
Equity is the short term for Actor's Equity which is the union for actors and stage managers. There are different types of theaters, some have union actors and some do not. All Broadway theaters are equity and only use union workers. Many regional theaters are equity but employ non-union actors in smaller roles to help them get their union status. There are productions of musicals that go out as "non-equity" tours meaning they aren't using union workers, although some have hired one or two union people.
If anyone ever tells you that you put too much Parmesan cheese on your pasta, stop talking to them. You don't need that kind of negativity in your life.