People were designed to perform physical exercise. Today we have so many conveniences that many of us or in conflict with nature. Through most of history humans had to walk, run and toil just to survive.
Hunting, fishing, searching and escaping were things our ancestors needed to do to live. Today we rarely need to do any of those things.We are lucky right? Well yes and no.
Most of us don't get the exercise we require. Even at the gym its not a natural form of exercise.
We are lucky enough to be able to choose the way we exercise. We just have to make some choices.
Almost everyone can walk. So if you are really unfit start there. Walk in places you enjoy like your yard, a park or someplace else.
If you love sports then that's a great option, although you have to protect yourself from injuries.
Working in the yard is another way to gain your health and stamina.
If you enjoy gardening then that will hardly seem like you are exercising, but you still gain the benefits.
The bottom line is that you should find something you take pleasure in and will give you some form of exercise. If you enjoy it then you will keep doing it.