You cannot, actually, choose what to do under certain circumstances.
It mostly depends on what’s the exact circumstance and what’s your role under that circumstance.
But you can choose what circumstances to be under, if you’ve got the three things below:
the healthy enough body to take you to go around in the world,
the strong existence-I to control what the doer-I devotes attention into,
and enough assets to support an basically satisfied daily life.