Best Co-op game you can suggest.

Not games like l4d or something like that.

So far most enjoable one was Nazi Zombie Army and Dying Light. I'm looking for good coop campaing games or even possible models for single player games which makes them to have coop.

Nah dude trust me its bad idea

I once played Skyrim co-op with a mod, It was so good (a bit buggy but funny as hell), if you like games like skyrim check nexusmods for the co-op mod), also Dungeon Defenders for tower defense and Killing floor for Zombie FPS, are my best suggestions

Far Cry 4 was very nice

Gang beasts is a awesome game! I highly recomend!! or Blood and Bacon its a fun game thats pretty cheap

PUBG Is the best game ever

acho que sim, viu ? qq coisa me avisa

I think Left 4 Dead is great. CSGO can be good but there's a lot of hackers and Gmod has the most amount of hours you can get out of it in my opinion.

Rocket League, TF2, GTA V, Ghost Recon Wildlands (Great Game), ARK: Survival Evlolved, Squad, Garry's Mod, Arma 3, Borderlands and Borderlands 2, Gold With Your Friends, Killing Floor 2, Portal 2, and Payday 2.

I ownall of these and played with friends in Coop

Portal 2 is the obvious pick but honestly - the Splinter Cell series are amazing co-op games. (Screw Conviction though, 30 FPS lock bollocks)
Get a pal to play Chaos Theory with, it's worth it.