in the first chapter of the manga a young boy whose mother is some kind of documentary movie director strays away from the filming crew and is lost in the snowy forest. There he meets a wolf who is later revealed to be able to speak (he is in fact some kind of supernatural wolf being able to form contracts with humans).

The boy then proceeds to forcefully form a contract with the wolf and is later saved by him. In the consequent chapters the boy is attacked by some kind of monster after leaving school. The monsters seem seem to feed on some kind of energy from humans.

The manga is quite modern (the drawing style is very modern and resembles manhwa more than manga).

It's a webtoon, I've only read the first chapter, but I think it is this one:

Wolf's Castle

Scanlated by EGS

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There's nothing to see here. Proceed with what you were doing or throw rainbows at random pedestrians.

not too sure but it might be Aflame Inferno
Its a Manwha by LIM Dall-Young (who also does manga I think, thats why you might have mistaken it...). Some things dont fit with your description though.
I dont know anything about the mother (cause havent read much of it and its been a while as well...). And the setting is not in a snowy forest but city.
But the rest fits perfectly. Boy meets talking wolf/monster, forms contracts with him to save his life and fights monster.
Already happens everthing in first chapter, so should give it a try cause description here on mangaupdates doesnt tell much.
Hope it helps

Yes, that's the one. Thank you)