The movie starts with a young, underprivileged teen named Kelly who moves, with her abusive family, into a housing project in Northern England. She meets some kids and becomes best friends with a girl and developed feelings for an older boy. The boy tells her he is running away to Southern England to find his birth mother and she decides to join him. Once they arrive, they meet some young men who sell them drugs. The boy ditches Kelly and she gets picked up by the police and returned home. She convinces her new best friend to run away again with her, back to the drug dealers, who had been kind to her. The girls go and meet up with the men who get them drunk and try stuff with them. The best friend ends up getting mad at Kelly and leaves. One of the men has sex with Kelly but realizes it was a bad idea as she is underaged. The men try to convince Kelly to let them pimp her out to random men. I can’t remember the end but I think she escapes.
Thanks for the reply, it isn’t London to Brighton but there are definite similarities.
It has some resemblance to “London to Brighton” (2006).
https://www.imdb.com/title/tt0490166