Should I tell them?

So I’m currently dating around and I’ve made it clear that I am single until I am formally asked to be a girlfriend. And the men’s responses were “as you should” , “same here” , blah blah. So, I’m starting to progress with one of them more than the others & I feel like of them all, he’s the one who’s more serious about a relationship, marriage , kids , traveling , etc. Just based on his actions. And it made me think, wait so what do I do when/if one of them asks me to be their girlfriend and I say yes? Do I actually tell the others “as you know, I’ve been dating around & I’ve decided to see where things go with someone that I’d like to focus on” or is that too much? I don’t wanna ghost them b/c that’s lame but I also don’t wanna over explain anything b/c who even knows how many girls they’re seeing also.