Jog/Walk

Careful. This is one of the biggest mistakes people make when they try to lose weight. Burning calories through fitness isn't an exact science. The numbers you see fluctuate and are generally an estimate because no two people are the same. Fat content and muscle content in the body are what really determine burn rates.

For example you said MFP says jogging at the slowest pace burns 632 calories (I will assume per hour). I found a reputable website that logs the same amount and type of exercise as 540 calories. A difference of almost 100 calories. Another website calculates the same activity "running - 5 mph" which is considered slow or jogging as 700 calories...again a difference of almost 100 calories.

Recent studies also prove that tech items like Fitbit are generally inaccurate 80% of the time.

Bottom line is this: You are on the right track. Eating less (and more nutritious food) and exercising more is how you lose weight. You also have to recognize that in order to keep the weight off you will have to continue to exercise and eat less, perhaps not as extreme but it is a lifestyle change required to sustain the weight loss. You never really stop.

Jogging may not be the best way to start out if you are overweight and out of shape especially if your knees give you trouble right away. That's your body telling you it ain't gonna happen!

Cardio (jogging) is good exercise but weight loss is vastly improved by weight or resistance training. You don't need to sweat profusely to lose fat, although it does help and is obviously good for your heart. Muscle is 3 times more metabolically active so the more you tone up or add muscle the more calories you burn...

Walking works just as well as jogging and is lower impact, just do it longer and work up to jogging if you so desire. Add some weights to your ankles and wrists while walking and you have a good workout. Wrist and ankle weights can be purchased in many places and you may even find a bargain online for some used ones.

Other activities to consider are chest high water walking (way more resistance in water), water aerobics and swimming. They are activities that are easy on the joints (knees) because you are virtually weightless.

Don't obsess over how much you burned. Focus instead on your intake of calories and just make sure you get regular exercise and forget about logging it in MFP. Eating back your exercise calories, IMHO, is a waste of effort because the calories burned are not generally accurate.

Go to it!