My personal experience: I haven’t been fucked by a man, but have been pegged by a woman and have sucked a man’s dick twice. So I can’t give you a firsthand account of being fucked by a cis man, but here are a few thoughts that might apply:

First, be VERY upfront with the person about everything. Set hard boundaries, let them know what you’re into and what you hope to get from the experience. Most people are going to be accommodating and good to you. Be sure to mention protection during this (if applicable)!

Second, you’re likely going to be very nervous, there’s no getting around that. That’s part of why the hard boundaries et al are important. If I’m being honest, the nervousness might make the first time less enjoyable. Take a little time after to think about what you liked about it, what could’ve gone better, etc. Remember that you’ll be more relaxed and able to enjoy the next time more, if you decide to go down that route.

Third, you’ll never know if you don’t try. It’s cliche, I know, but I am SO glad I tried.

Also, I don’t know where you live/what the women are like there, but every woman I’ve ever talked to about pegging has been up for trying it. Most of those women were queer though, so do with that information what you will lol.