He needs to give up on trying to be social, at 5'1 it will get him no where but being a Jester.
No one will respect him.
He needs to go loner, if he has a job don't talk to anyone unless they talk to you and only then keep to minimum interaction (that is a general rule for Manlets and incels).
Just go about your business and try to look competent at your job or whatever you are doing so you just blend in with the environment.
Just accept that whatever you are doing you will be doing it alone, only way not to get crushed by life.
Then find some copes you can do alone or online