I COMPLETED MY MTECH(CAD/CAM) IN JNTU UNIVERSITY INDIA AND I COMPLETED PROJECT ON COMPUTATIONAL FLUID DYNAMICS?

AND I WANT TO DO PHD(USA) IN CFD .COULD YOU OFFER ANY RESTRICTIONS TO DO MY PHD(USA) IN CFD.IS THAT IMPORTANT DO MS IN US TO PURSE MY PHD.HOW MUCH GRE AND TOFEL SCORE IS REQUIRE FOR PHD IN US.