What Are American Revolution And French Revolution Similarities?

Actually, not many.  The French Revolution was a very bloody civil war where people turned on their fellow countryman.  It was a revolt against a system whereby a king, answerable to nobody and with absolute power, ruled the country were the poor people were starving and oppressed by an exploiting aristocracy.  It was a bloodbath which ironically produced leaders who were even more cruel and the people they replaced and ultimately gave us Napoleon -- who wanted to be an emperor!
The American Revolution resulted from settlers in America paying taxes to London without having any representation or influence in London.  Hence "no taxation without representation".  Most revolutionaries didn't want independence, they wanted to be given what they regarded as their rightful status and local autonomy without being at the disposal of a country ruled by King who didn't speak English anyway!  During the Revolutionary War, more settlers actually fought against the revolutionaries than for them and many of the so-called English soldiers were in fact Hessian mercenaries -- more German speakers!