14 pregnant, crazy step mom wants baby, aunt offered for me to move with her

Hello, I’m 14 and pregnant. I understand the mistake I made, but i would never kill a child. I will do everything i can to raise him. Im 25 weeks, but i have a problem. My Dad’s soon to be wife is crazy. She’s completely turned my dad against my boyfriend and I. My dad has only been with her about 6 month. I have already told her multiple times she’s not getting my baby. She thinks my Dad will force me, for one legally they can’t and two I’m very stubborn. She even told my close aunt that when i got my sonogram done last week she loved seeing her baby. She is consently going through my phone and lying to my dad saying I’m saying stuff that I’m not. Her whole family is rude it to me about . There’s no way she’ll get my child, But she’s extremely controling over everyone. I’m affaid that if she doesn’t leave my dad once she realizes she’s not getting the baby that she’ll be demanding with my baby. or even mean to him, I know she’ll try telling me what i can and cant do with him. she already tells my Dad im not aloud to go to families houses. My main question is how hard would it be for me to move into my aunts house. She has a spare room for the baby and I, which i dont have at my house now i share with my younger sibling. They’ve offered to help me with whatever i need. also babysit while im at school. I do not want my dads wife babysitting because she’d probably be mean to my son. I’m trying to do whats best for him, moving in with my aunt if she stays is mostlikely best. How hard and what would i have to do to do so?