how do I START my car in-35 degree and it say to heat up engine whereis the plug to heatit up
Just start it. Cars are tested to -40. If you don’t have a block heater installed there is nothing to plug in.
All is revealed in your owners manual. Just pick it up and read it!
Block heaters are options. Your car may or may not have one.
Owners manual will tell you location of the cord.