Potential first lesbian experience next weekend!

I’m in a very happy 4 yr relationship. I’m 25f and my partner is 38m. I have no doubt in my mind that I could easily spend the rest of my life with him - however, I want to have sex with a woman before we get married. (Not even engaged yet!)

Ive made out with a girl years ago and I loved it! Could have easily taken it further. Next weekend, I’m spending with it with a couple I know who are gay just having drinks at their house (us three only). The more feminine one who is Bi, has told me many times that she thinks I’m one of the most beautiful people she’s seen..... so I feel like that’s hinting she would be keen....

I’m really good friends with her girlfriend but I have no idea if she would be keen or not however I know they do have the occasional threesome.

My question is..... should I go there? How should I go about it if I do!? 😁