Being a top for the first time

Long story short, I'll probably top for the first time in the near future and I would like any advice I could get.

Now, if you feel like reading: I (22ftm) have been going out with this guy (23m) for like a month now. Our dates have been becoming more intimate, but nothing sexual has happened yet.

On our last date, we talked about it, he said he hasn't really had any satisfying experiences before, so he doesn't really have any preferences yet. And I've always been a bottom, it's not something that brings me dysphoria (only had vaginal sex, but have experimented with anal on my own and enjoyed it). But I've always been curious about topping.

The thing is, I don't have much experience overall, I could probably count on my hands the amount of times I've had penetrative sex. I also have a hard time actually reaching an orgasm with a partner (no problem when I'm on my own), so I can't even imagine that I'd be able to while topping. Now, for me, sex isn't necessarily about orgasming, I enjoy the process and I feel good about pleasing my partner, but I know it's something that makes both me and my partner anxious.

Anyways, I had a packer that allegedly can be used for sex, but I've experimented on my own and I feel like it might be too small (9cm that can penetrate) and the head is a bit too soft, so it's difficult to get in, especially for anal. But what would you recommend for a packer/prosthetic/whatever you wanna call it. Also, I'm from Brazil, so many brands might not be available, so if you could say the specifics about it (size, material, something else I should look for...) I'd be really grateful :)