Welcome to BYC!
Its a bit hard to tell in these photos, if you could get some more, more from the side that would help.
I think at least the one on its own may be a cockerel, and most likely one of the others as well.
I think they are both cockerels, a lot depends on age, as a pullet near laying would have the same amount of comb as a 10 week old cockerel. However, they both look quite young, so I'm going with cockerels.