Do you have a cherry pitter?
Doing it with a knife makes more of a jicy mess.
We used to pit cherries by sticking a certain size old fashioned hair pin into a cork. The hairpin was just the right size to "hook" the pit and get it out without injuring the cherries too much. But then we did not freeze them, only canned them. Not many people in the 1930s froze food an the olf rridges used to have a very tiny feezer compartment, usually just large enough to hold two ice cube trays.
It also depends on what you want to do with the cherries but you can try. If you can get cherries every year I would invest in a cherry pitter, they are not that exoensive.
If you want them just for pies and such, pit them and freeze them in food saver bags or freezer bags.
For snacks I would freeze trhem whole, with the pits left in.