@Kerosene silent hill 2 is an obvious one but if you haven't played it you should. It isn't that scary all things considered, the horror is a lot more grounded so it kind of wraps dark tendrils around you instead of just whipping a spooky dick out ya know?

The remake is alright but it is way too long and misses the vibes a little imo. Either emulate the ps2 original or get the enhanced edition running on your pc.

If you want something that will make you piss and cum, get MADiSON and turn off the MC's voice. That game is the scariest game I've played in a long time.

Outlast is another pretty good recommendation. The second one sucks but the whistleblower DLC is pretty good.