How can one help friends who watch bad movies, listen to music, and neglect prayer, despite attempts to remind them and encourage them to watch Islamic lectures?

Good company is a legitimate religious requirement, and a Muslim should strive for it to be saved from tribulations, and should only associate with a believer. The example of a good companion is like the bearer of musk, and a bad one is like the blower of bellows.

If a person cannot find a place to live except with those who are not righteous, there is no blame upon him, provided that he does not sit with them when they are committing a wrongdoing. If he witnesses a wrongdoing from them, he should forbid them and remind them; as Almighty Allah says: "And when you see those who engage in [blasphemous] discourse about Our verses, turn away from them until they engage in another discourse. And if Satan should cause you to forget, then do not remain after the recollection with the wrongdoing people. And those who fear Allah are not accountable for them in anything, but [theirs is] a reminder that perhaps they will fear Allah." If they do not respond, he should continue to remind them with kindness and supplicate for their guidance. He should not prolong his sitting with them beyond what is necessary.