As shared by Altamash sahab above, the best struggle (jihad) one can do against an unjust ruler is through words. This must be done while still upholding the law.
Please consider the following words reported to have been said by Prophet Muhammad SAW in this regard:
You should listen and obey them even if the ruler strikes your back and takes your wealth, even still listen and obey.
Source: Sahih Muslim 1847
No, as long as they establish prayer among you. If you find something hateful from them, you should hate their actions but not withdraw your hand from obedience.
Source: Sahih Muslim 1855