both very similar 1.- you might say after getting over an illness or an operation 2- you might say just as you have learned to drive a car

In many situations you could use either. One possible difference is where you are saying that you "can" drive but are not talking about your ability. for example: "today I walked, but tomorrow I can drive a car" (maybe because it is then available). You can only understand this fully by seeing many examples. good luck.