I'm a 31-year-old male what the best way to lose weight how many days should i exercise?

Katz book: Disease proof by david katz, md is a good book for overall health. It contains lots of useful information about the way we eat and is written very clearly. Focus more on health and lab results than the number on the scale. Walking can be a great benefit also. You can do it. Please see your doc first. I see that you have had back issues. Low carb and high protein works for some also.