Start looking for new positions immediately and make this your primary occupation.
If you can cope with the working conditions, consider staying until you find a new position. Set a high bar for this. Your mental health matters more than having the job, presumably. Workplace bullying might very well be illegal where you are; consider gathering evidence and submitting it to the local police or relevant university services, if those are reasonable options.
If you can not cope with the position, leave.
In any case, tell your former advisors and other senior people whom you know that the person is abusive. You should have been explicitly warned before going there. Spread the word among all the people you know well, and who trust your judgment.