First and foremost, you need to get your diet in order.
Figure out your Daily Energy Expenditure (DEE) in order set your calories. In order to do so, you first need to determine your Basal Metabolic Rate (BMR), which is how many calories you would burn if you didn't do nothing.
BMR = 66 + (13.7 x weight in kg) + (5 x height in cm) - (6.8 x age);
Your BMR would be: 66 + (13.7x105)+(5x175)-(6.8x21) = 2223;
*I don't know your height so I used mine, 5'9"
Now figure out your Sedentary level1.0 - Sedentary (couch potato);
1.2 - Very light activity (pencil pusher or puter geek);
1.4 - Light activity (pencil pusher who likes to go on walks);
1.6 - Moderate activity (pencil pusher, but likes to workout);
1.8 - High activity (physical job and trains);
2.0 - Extreme activity (construction worker and trains diligently);
DEE = BMR * 1.6 = 3557;
Your DEE is your baseline, no if you want to cut start out at a 10% decrease, so you should start out at about 3000kcal
The as far as training goes, You can do a MWF approach using weights, and THS preform HIIT.
Supplements, I would consume BCAA's, support T-levels, and control cortisol.
Your only carb sources should be veggies and fruits, and maybe other source of carbs for post-workout.
Bump up Fish oil intake.
Consume 1.5g protein per lb.