A quick note on exercise
When it comes to exercise, it is important to do the correct exercise for your body shape and size. Too many people attempt the wrong exercise only to find that things prove to be far too difficult and so they quit really early.
For example, you wouldn't try to run a marathon without a lot of practice and conditioning first.
Classic exercise mistakes are things like trying to do press-ups or sits ups when still seriously overweight. You may need to lose substantial body fat from around the abdomen before sits ups are possible, and if you are really heavy, even a season's athlete who is familiar with press-ups may struggle to do even one if he were weighted down the same.
So, for exercise to start with when trying to get fit and lose weight consider the humble walk. Start there, and increase the pace and length of the walk as your body gets stronger and familiar with the exercise.
Only as your cardiovascular fitness improves and your body strength increases should you consider increasing to attempt jogging or running.
What you should really consider is taking the advice of a suitably trained fitness coach who can show you exercises that keep apace with your level of fitness and body size.
If you try too much too soon, you will surely fail. Not because you have a character weakness, but simply because you have taken on too much too soon.