Where to find detail drawings for engines?

Hoping someone might be able to help me w/ this. I'm trying to do a project of a detailed engine, but I dont have the slightest idea on where to get part drawings, etc.

Not looking for any specific kind of engine, just trying to see if I can get some help getting pointed in the right direction.

Please do not open any links and do not make calls (including WhatsApp) to any numbers from messages sent by accounts such as Grabcad Verification, etc. - these are phishing ones. Please do not make any payments. Our security team is currently working on a solution.