How do I [22F] get more comfortable with sex?

Full disclosure, I haven’t had sex before or had a serious relationship. I want to lose my virginity and I have the opportunity (after it’s safe) to lose it, but it’s to someone who would be a fwb. We talked about sex for a few hours over the phone and it led me down a rabbit hole of self doubt lol. I’m now scared that I’ll never feel comfortable enough to have sex. Whenever I engage in something slightly sexual (sexting or even making out sometimes) I feel regretful and used for some reason, like even if I was enjoying it i feel like I wasn’t doing it for me. I want to lose my virginity and connect with someone this way but how do I get over that feeling and feel more comfortable with the idea of sex and not feel ashamed of my own sexual desires? I know it’s normal for people my age to have never had sex, but I’m afraid if I don’t get over this that I’ll never find someone I’m comfortable enough with to do it with and it’s so frustrating. I just want to relax and have fun and be more confident in my sexual side. I feel stupid and naive for being so self conscious and anxious about it.