If necessary, close your eyes and ears. What you cannot see and hear by you cannot hurt you. When you cannot stand what’s happening on the screen, then close your eyes and place your head in your thighs and cover your ears with both hands.
Use “safe” signals with friends. If you want to make sure you open your eyes at the right time, then ask your friends to pick you up when things are safe to look back on. Again, do not ask the help of your ignorant friend who will poke you in unexpectedly when a piercing scene occurs.
Leave the place if you really do not enjoy it via streaming movie. No one is forcing you to watch the movie (hope), so off you go if you hate it. Wait in a room that has good lighting until the movie ends so you do not have to feel afraid anymore. If you really hate horror movies so you can not watch them, then you should not be embarrassed. It means that you are sensitive to injury and violence and have a great empathy for people. Tell this to your friends if they force you to watch.