Hello, Indalecio. You're correct, 'creep out' is a phrasal verb. We use it informally in the United States. I'm not sure if your use of 'creep out' would mean the same as scaring someone. This is because 'creep out' can also imply you are disgusted by something (in addition to being afraid or uncomfortable). What context did you want to use 'creep out' in? I have also included some example sentences of the phrasal verb below:
1. He was creeped out by the sight of blood.
2. Spiders and snakes really creep me out.
3. The woman was creeped out by the strange man's behavior.
4. Aren't you creeped out walking home alone at night?
5. Joe was creeped out by the house because it appeared to be haunted.
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