How am i suppose to ask a girl out who is with her friends constantly and got her phone taken away for a month?

go up to her when shes wth her friends. ask if you can talk to her alone. say something sweet, like 'ive been thinking about you a lot, i care about you, will you go out with me?' or something like that lol. if she says no, dont be too hard on yourself. give her some time, and than ask her again to see if she changed her mind after having some time to think about it. dont be annoying tho lol. she might say yes, in which case - nice job!