How could I let my floor neighbor I would be interested for sex?

I'm a 27F, and I live at the top of an old building in France. In the other flat on my floor live with two pretty men who seem in their early 20s. We occasionally meet and they are polite and friendly. It's only earlier this year that I've lost my v card, and I'm currently into exploring my sexuality. So my mind has drifted into the neighbor fantasy? (Is that a thing?) Anyway, would it be unwise to try anything? But if not, how do I even go about it if I meet one of them in the corridor or elevator?? (Dont know if I would dare to go knock at their door for this) I'm maybe older but so inexperienced in that field...