First off, welcome to talkingreef..
second.. yes, those are anemones.. they are bad/pest anemones
they are called aptasia, and can be a real nuisance
there are a few ways to get rid of them.
the most natural way is to try getting a peppermint shrimp as they naturally feed on these things.
another step, is to inject them with something called joe's juice (some
LFS sell it, but you can make it your self) or you can make a
kalk paste, and cover them in it.
if they are all on one rock that could be removed, you could remove the rock and bake it.
this will kill everything in the rock including those little buggers.
the beneficial bacteria that you want in the rock will come back, but if the aptasia are only on that rock you will be good to go
