You do not discover what you can handle by staying where nothing is required.

Capacity is discovered, not predicted. Sitting in a situation that asks nothing of you, you have no way of finding out what you could carry, and the estimate you carry around is based on nothing but imagination. People routinely underestimate themselves for years on this basis.

You do not need to overturn your life to test this. Choose one thing that is genuinely a stretch and see what happens. The point is the information rather than the achievement. Whatever the result, you will know something about yourself that no amount of thinking from a comfortable position could have told you.