They can jump. in L shape. the square they jump to has to be empty. so if a knight is on a1 or bottom left then it can jump to b3 or c2.
Can knights jump over pieces?

No, no, keep playing without knowing the rules, your excellent ratings could suffer if you lose your innocence.

They can jump. in L shape. the square they jump to has to be empty. so if a knight is on a1 or bottom left then it can jump to b3 or c2.
yes but do you have to clear space for the horse to gallop?

No they can trot or gallop even if obstacles are in the way. as long as the target square is empty. otherwise the horse will have to neigh and kick the occupier to make space

As long as they have a run up, they will be able to jump over everything, provided you make a neighing noise at the same time. It is advisable to give your opponent compact lead knights so they will be more reluctant to do so.

It depends, they can jump pieces but it is kind of irrespectful to do so, I usually ask my opponent to move his piece a turn before so my knight doesnt jump over it, I like respectful gentlemanish chess.
If you don't care about manners you can surely jump the pieces, but that is just unethic and irrespectful.
lol !
or do you have to clear space for the horse?
thanks in advance