The Blynk Blink example is simpleā¦ a car or rover is not 
And yes, many have done it. Search and ye shall find.
We will assist as you learn, but we all have our own projects to work on, so you need to start yourself off with some education about how Blynk works in-order to work with either your own code or modifying someone elseās to fit your needs.
See similar advice I just gave to another user who started off asking without showing some efforts firstā¦