I have a bunch of these things in my inventory called wishbones that can supposedly grant wishes. How and where do I use these things?

I'd advise that you read the announcement of this new feature on the News page. :)

why did i not get any wishbones after defeting 2 pheasents, all they dropped were claws

Midnight, there's only a chance for bird prey to drop wishbones ^^ So sometimes they won't drop wishbones

Midnight,

Pheasants can drop claws or wishbones. You're not guaranteed to get a wishbone from them. Sometimes it's just claws.

Blue,

There is some information on the August 25th news page that explains which birds drop them and how you can manage your wishes. If you want to use your wishbones to help someone else with their wish, go to their den page and there should be a button that says "Wishes" right under their memorial.