So you clearly understand that you are not studying enough? Don't get too flustered....you are no different than the other 50% of students in their early years. It's perfectly normal to not understand the amount of work that goes into an engineering degree.
The question is this....what are you going to do from this moment forward? You don't need to start fresh, you need to be an actual college student. If it were easy, everyone would be doing it right? And it would be worth a damn thing.