Only do physical exercise if you are OK’d to do so by a medical doctor.
Get adequate sleep and good nutrition.
Lay off the junk foods, tobacco, alcohol and other recreational drugs.
Stay as physically active as possible. Find an activity that is right for you and exercise regularly and intensely at times. At least do a little bit frequently. But don’t do a lot lot once in a while.
Make physical exercise a part of your routine. You brush your teeth and clean your body daily and you should also do some physical exercise daily.
I do 9 different calisthenics 3 to 5 days a week, paddle an outrigger canoe 40 to 50 miles per week (good low impact exercise) and hike 18 to 20 miles per week. (I’m 69 years old).
Good health! Stay strong!