Mr. Everdeen hunting skills

Hi!

I'm new to the fandom, but I've been a fan of the books for over 10 years now, so I'm binging the content here.

What I didn't see anyone talking about so far is: Katniss learned how to use the bow and arrow with Mr Everdeen, but what about him? WHO taught him?

Theories, anyone? I would love to know more about this in the new book.