The only possible way to do that will be to follow an extreme low-carb diet for the entire 2 months. Less than 20 - 30 grams a day. One day a week, after a hard workout, eat up to 150 grams, but that's all you get. Your diet should be about 60% fat, 35% protein, and 5% carbs. The majority of your fat intake should be in the form of mono-unsaturated and poly-unsaturated fats. If you weigh around 200 lbs, you should shoot for about 1700-1800 calories a day.
In addition to this insane diet, you'll have to incorporate an insane workout program - so I hope you're already in very good cardiovascular shape. You'll have to hit the weights hard, but super-set EVERYTHING (preferably an upper and lower body exercise in every super-set - and ALL COMPOUND MOVEMENTS - no isolation moves) and rest little to none throughout your entire workouts - which should last about 45 minutes each - 3 times a week. In addition, you'll need to include 4-5 HARDCORE cardio sessions each week. Slow-go cardio will be a waste of time for you. You'll have to incorporate intervals into your cardio, and even the "rest intervals" should remain slightly difficult. Follow your 15-20 minute interval session, with another 15-20 minutes of steady-pace, yet still difficult, cardio.
Do this and you can lose 20 lbs in 2 months, and 90-95% of it will be fat loss.
As for a "Potent Fat Burner"... There really are none. In 2 months, one of these products "might" help you lose an additional 1-2 pounds, but you'd be lucky with that. Really, find one that gives you a good energy boost, because you're going to need it...
Ps., if you're not already in great physical and cardiovascular shape, then please don't even bother with a program like this. You could die.