Your 19-year-old son is legally an adult. Forbidding him to do anything makes it sound like you’re treating him like a child.
If he’s 19 and still living in your home, instead of forbidding him to be out late, let him know that these are your rules, and as long as he’s living under your roof, you expect these rules to be followed. If for any reason, he needs to object to these rules, he may request an appeal. You can talk like two adults, to discuss why your son thinks your rules are unreasonable, or why he should be allowed to not have to follow them. You can then reach an agreement together as to what’s allowed or not while he’s still living with you.
Also make sure you’re reasonable. If you son doesn’t come home until 11:00 p.m. and you get upset with him for waking everyone up when he comes home late, but he tries to tell you his car broke down, and you wouldn’t answer your phone when he tried to let you know, then you’re being unreasonable in that situation. Make sure you address the situation as it happens so he will know what constitutes reasonable and unreasonable.
Even though he’s an adult, in the end, he’s your son, and you’re the parent. You want what’s best for him. What’s usually best, is to be able to communicate.