Stuck in the middle

Backstory: April 2019 I met the man who is now my fiancé. December 25 2020 we got engaged. I'm 18, he's 20, we've both graduated high school. Problem: My fiance and I are ready to move in together. We've been engaged for several months now and haven't really got to enjoy it because of how my parents reacted. My family/parents have very strong beliefs and I don't always agree with them. They don't approve of our engagement (nobody knows in my family except my parents because of how they'd react) and they definitely wouldn't approve of us moving in together. They basically believe that you should finish college and wait a while before even thinking about engagement. However, my fiance and I have been together over 2 years and we had both talked about it and we were both ready to take the step. We were so excited, just like we are about potentially moving in together. But, idk how to make it work with my family. It's ripping our relationship apart in all honesty because we've both been under so much stress and pressure from this problem and it just never goes away. I just don't know what to do...