Diet = get this in order first and track your calories (try myfitnesspal to start). Most brehs underestimate how much they're eating.
Cardio = if you can't run a couple of miles without stopping, all the lifting in the world is pointless. Unless you're trying to be some World's Strongest Man contestant, get your cardio in....swimming, basketball, jogging etc. And don't fall into the HIIT trap. Focus on getting healthy before worrying about performance. Stamina and a low heart rate require longer cardio sessions. This will make your lifting workouts "feel" easier as your body will pump blood more efficiently.
Lifting = 3 to 6 sets per exercise, generally between 5 and 10 reps per set. If you can do 10+ reps at a particular weight, increase the weight. Save time and focus on compound lifts like squats (many variations) bench press, bent over rows, shoulder press etc. There's no one size fits all plan. But focus on form and technique first. The gains will come.
