How do I break up with him ?

I wanna break up with my boyfriend . We’ve been together for 3 years and 2 months . We started dating in 2016 . The first year everything was wonderful . We ended up breaking up for a week after we turned a year and 1 month . We got back together and after we made 2 years and 4 months I found out I was pregnant ( I was 16 and he was 17 at the time ) I moved in him with we have the same birthday month July he turned 18 I turned 17 . I moved in with him and the first week was great after wards he changed. When my mom started talking to me again they would always invite me to go out with them and I would say yes but he would get mad if I left the house or if they picked me up . He would always say I can’t go out because I had to wash his clothing and clean the room and mop and etc . I knew that was my responsibility but even if I did it he wouldn’t let me go out . Unless it was with him . During the first 4 months of my pregnancy instead of gaining weight I was losing weight I went from 155 to 130. Then i found him texting other females that he missed them and wish he was with them instead of the bf they had . He was asking for nudes and trying to buy nudes from a page on Ig . I ended up moving back with my mom for the rest of my pregnancy. I just had my baby 1week n 1 day ago . So she’s fresh outta the belly . And he wants to take her to the fair and out to eat but I don’t want too just because she’s too small. And can get sick with a lot of people there .ever since Monday all we Have been doing is arguing really bad . I must admit i sometimes start too.

I recently found out my baby has a tongue tie problem and I wanna be able to do it while she’s still small but he wants to wait and slee started arguing about that too.

I have tried to sit down and talk with him and he Dosent wanna listen or he ignores me and tries to change the conversation. I don’t know what to do I just wanna break up with him it’s not the same anymore. Help me, help me get the courage to break up with him. I turn 18 this year and I also graduate. So I will be working to support me and my baby after I graduate .