Doubt related recursion

I have watched several times video of get board path but I am not able to understand it. please explain it?

Hi mansi,
I have solved your doubt on Chat window.
Please mark the doubt as resolved or if any query then revert back here.

I hope I’ve cleared your doubt. I ask you to please rate your experience here
Your feedback is very important. It helps us improve our platform and hence provide you
the learning experience you deserve.

On the off chance, you still have some questions or not find the answers satisfactory, you may reopen
the doubt.