Planning from scratch

Hello,

I haven’t started studying for the GRE at all but would like to take it in the summer (July/August). I just joined GregMat+ to start my prep. I was thinking of following the 2 month plan. Is this a feasible timeline? How many hours a day will I need to dedicate in order to finish each day’s materials? Should I be using other resources to prepare for the exam outside of GregMat+? I am aiming for a 325/330 total score. Any advice is greatly appreciated since I am very new to all this. Thank you in advance!