I need advice

So I (15F) grew up in an entirely atheist household, where Christianity was viewed as ridiculous and stuff like that, but now I've accepted God as my lord and Savior, and I don't know what to do, because I know if I try to read a Bible or go to church and my family finds out, I'll be criticised and alienated. It's the same with most of my friends, they are heavily sinful, but I don't have anyone else. And my boyfriend is constantly trying to do stuff with me (havnt done it yet but like second base idk) and I'm scared I'm going to go to hell. I don't know what to do.