what should i do?

u must go on from there

Often when people are unhappy in their job, they begin looking for new ones while still employed. For some reason that makes you a better commodity in the job market. Sort of a proven track record. Where I live often the applications will ask, "May we contact your present employer" and I often say "NO" if they do not know I am looking anywhere else. If you already have another job lined up, and the pay is sufficientm, and you really hate your boss, you should "go for it" couldn't be any worse than where you are now. Good luck.

I'm in a similar situation, only problem is I can't find another job. The way I see it: put up with the crappy job now until you are SURE you have another opportunity that will be better, that way you have nothing to lose.

find/apply a new job first on other place, after you confirmed that you are accepted on that place then you can resign from your work now