It changes into juegan because ue is an exchange of (an) in the present form . I hope it helps !!
Females don’t participate in lucha libre
Puertas I believe that’s the plural form (plural means more right lol) if it does that it’s Puertas
Mis amigas leen mucho. A ellas les gusta la serie de Harry Potter.
Ellas because they're female, Ellos would mean they're male. Hope this helps :)