Where do we use do while loop?

Answer 1

In all situations where you want an algorithm/code to be run at least once, for example when you have an animation in a game which runs until the end of that game. Then you have to render the graphics at least once and then continue until some conditions are met.

Answer 2

for example it maybe use in program of ATMs,that means when you use an ATM, you should at least input once ;)