My friend used to play Conan but his screen broke, apparently screens don’t like getting punched. Now he’s back but his games keeps crashing, he get’s a pop-up saying that he needs to verify the integrity of the files.
It makes the game near unplayable, crashing ever so often.
None of us are techwizards, is it drivers? Some cache-like folder to delete?
Go to steam, right click on Conan Exiles and choose Properties.
Then from there choose Installed Files and Verify Integrity of Game Files.
This process will take a while but hopefully it should solve your problem. Assuming you are playing on Steam that is. If not, then I have no idea how to get there. 
Yes, though the thing is after that he can only play 5-10 mins
It means something is crashing the game while you’re playing. The information you provided and what you’ve said has led to this conclusion. I think the problem is an old mod. Uninstall all mods and clean them.
While the game is open, something is happening in the background and the game files are getting corrupted. It’s like a mod trying to update itself.
Get rid of mods and reset battleeye.