I need advice asap☹️

Laura • Momma to aleyna💛

So I recently figured out my boyfriends instagram password (he doesn't know that I know) and I went through his Direct Messages and I found out that he's been sending other girls messages and how he wants to get to know them! I'm 19 years old and currently 7months pregnant and he is 21 . But I really don't know what to do☹️ I'm supposed to move in with him this Sunday.. I had the balls to message one of the girls that he tried talking to and she actually was nice enough to help me out and keep the conversation going with him... and apparently he denied me and my baby! He said he didn't have a girlfriend ..... the girl the. Sent him a picture of me and him together! He then said that me and him were having problems and that I was pregnant... but once again he messaged another girl and told her the same thing that he wanted to get to know her.... I haven't confronted him about it because I don't know how to do it.... i don't know if I should even move in with him... I honestly just want the best for my baby... but can I get any advice ???