Why do people think female friends amounts to a girlfriend?

I see this advice get thrown around a lot, especially on this subreddit. I’m 17 and I’ve never had a girlfriend. Anyways, I’ve always heard the advice to “be friends with girls” or whatever. Most of my friends at school are girls. I’m in a group chat where it’s three girls and me, and it has not helped me get a girlfriend. I think the advice is really misleading. Plus, as a girl, why would you want to date a guy who has a bunch of female friends? That doesn’t make any sense. I’m pretty good at talking to girls—I have all sisters, no brothers, and most of my friends are girls—yet I still don’t have a girlfriend.