There are parrys...
There are redirections ...
There are strikes....
But there are no blocks in karate .... unless you are looking to injury yourself?
Kicks? Well, that is a matter of learning reflex timeing to parry, redirect,or strike. In essence, if there are kicks, then there is imbalance present, and in the openings that present imbalance there is opportunity.
A person who is great at kicking has to be twice as fast because of the time it takes to present the kick and recover. This means, one should work on timeing to become as fast or faster than the kicker without kicking. When that happens .... there are more opportunities, aren't there?
As far as learning blocks .... forget about it, they are not blocks. Stop thinking in those terms because it is a dead end.