Question

Loop button is used to repeat the animation infinite number of times ​

Answer 1

Explanation:

Go to the animation and set it as looping . In the Animation window look at the bottom for something that should say 'Default' - it's a drop-down menu with looping options (Loop starts the animation over, PingPong plays it back and forth, Clamp Forever freezes the animation at the state of the last frame etc.)

Answer 2

Loop the animation for a single element

On the timeline, click the Set animation repeat button on the animation layer that you want to loop. In the pop-up menu, select an option: Infinite - The animation loops infinitely. ___ times - The animation loops to play the specified number of times in total.