I'm terrified to talk to my dad

I'm about to start shaking I'm so scared to talk to my dad. I'm 16 and about to move out of my maternal grandparents house and move 4 hours away to live with my boyfriend and his family. I only see my dad once a week although very rarely at this point as he doesn't come over as much to visit. My mental health is terrible and I have tried every option I can and nothing is working/improving me at all, the next thing I can try is a new start hence moving away from home and in with my partner. It's happening in about two weeks and I still haven't told him. I don't know what to do. He's coming over soon and I'm telling him.

I feel like i should just back out and not even bother trying to move cause I'm too scared to tell him. I first thought of just paying the $100 every week to take the train there and back every weekend just so he never finds out I moved. I really don't know what to do. I'm so nervous.

Has anyone else done something like this?, or had a bad reaction from parents when they were told you were moving out? Anything is helpful at this point, a couple details have been left out as I'm so nervous I just keep forgetting stuff, any questions I will answer the best I can. Thank you