@Jennifer3120 Yes, shared accomodation listings can state that they only accept the same gender as the host.
I'm a single female home share host who accepts all, and my male guests have all been sweet and respectful, but I raised three daughters and I totally get it that a teenage girl would feel not okay about sharing space with men who are complete strangers to them.
In fact, I would not have hosted when my girls were little kids, either. I would feel like I had to keep a constant vigilant eye out. I could imagine them wandering into the guest's room, just out of friendliness and curiosity, and that would freak me out unless it was a female guest who was obviously a really nice, normal person.