IdiomCenter.com

bite the bullet (to force oneself to do something difficult or unpleasant that you have been avoiding doing; to be patient and wait when you do not want to wait; to make a difficult or painful decision; to take a difficult step) — стиснуть зубы, крепиться, терпеть боль, горе и т. п.

Терпи, казак, атаман будешь! и
Терпи, казак, атаманом будешь!

Used as words of encouragement to mean you have to be patient and wait or withstand pain / discomfort knowing that it will get better in the future.

см.
[bite the bullet]
[stick it out]
Never say die.
≅ It's a great life if you don't weaken.

Ср.