How to use 'N' number of for loop concept in SQL Server.

You have to implement cursor for doing this please see below code for cursor

DECLARE CursorName CURSOR FAST_FORWARD

FOR

SELECT collist

FROM tbl1

OPEN CursorName

FETCH NEXT FROM CursorName

INTO @Variable1

WHILE @@FETCH_STATUS = 0

BEGIN

//Repeat code for next level

FETCH NEXT FROM CursorName

INTO @Variable1

END

CLOSE CursorName

DEALLOCATE CursorName

For more clarification share script code and your requirement in more details.

As per my understanding , you need to check recursive cte in sql server

https://blogs.msdn.microsoft.com/craigfr/2006/07/26/nested-loops-join/

Please explain your issue in details (in terms of what is expected output and what are you are trying to do) ...