Fear of infidelity

I (20m) am currently single and not looking mostly due to being in the military (I have been told horror stories about relationships in the military).

I have been struggling with a bit a insecurity i have the last time I had a girlfriend was when I was 15 and I've been single since I can't do well when it comes to conversation let alone getting a girl to like me on that level, even then I always wondered if I got into a relationship infidelity would become a problem what if she cheats on me how will I be able to tell the signs that she's cheating how will I react if I find out or what if it happens when were married(which I know is worse).

My dad cheated on my mom multiple times and even had children with two separate women ever since I've tried to distance myself from my dad cause he was also abusive. I also hope on things like reddit and youtube and check out stories of things like cheating wives and failing marriages and I think it's psyching me out more.

Idk what to do how can I overcome this problem please help.