It is very important to work your muscle as this is what burns the most energy in your body. Larger/denser muscle = more calories burnt while doing daily activities which means you should lose more fat and keep it off for longer.
Doing intense cardio is very healthy for your heart and lungs, but only burns calories while you are doing the exercise. When you lift weights, you not only burn calories while you are training, but for hours after as your body kicks into gear and starts repairing tiny microscopic tears in the muscle tissue, the more this happens, the more tissue is repaired and this is how they grow.
Another reason why resistance training is better than just cardio for fat loss imho
Surely some more knowledgeable people will give you more detailed diet info. Just eat clean, lean meat, veggies, eggs, beans, almonds/natural cashews etc. Supps are only there to supplement your diet so get that up to scratch and you wont need them
Good luck
Gary