Kindly ask your son to move out. If he doesn't do so immediately call the police so they can tell him he is trespassing. If he doesn't want to leave with the officer telling him to get out, the officer can escort him to a new place called jail.
If your son is 18 you can ask him to leave the home. I do not think you have raised the requisite facts which would support the issuing of a Temporary or Final Restraining Order.
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