As the title says if my character walks over an actor he kicks it through the floor and sometimes he is thrown in the air or he does some kind of weird dancing, how can I stop this? 
You could set the small actors’ collision settings to “overlap pawn” to have your character walk through them. Alternatively, if you have “simulate physics” on for them, you could try lowering their weight to no longer have them affect the character as strongly.
sorry i dont know but you have to show me that!!!
“overlap only pawn” or “ignore only pawn” makes the actor go through the floor
unreal has the least intuitive collision grid ever btw