Autuomatically adding Rows with a formula

A formula will not do what you require.  The only way to insert rows like you reference is to use VBA code (macros).  The request you have is a fairly common one.  If you search the internet you will find different variations of the same answer.  You could use a macro linked to a command button or even a worksheet event that triggers when you type a number into a specific cell.  Here are a few different variations of what your trying to accomplish (I think the first one is closest to your requirements):

https://analysistabs.com/excel-vba/insert-rows-worksheet/

https://stackoverflow.com/questions/17588158/excel-2007-macro-insert-x-value-of-rows

https://www.exceltrick.com/how_to/insert-multiple-rows-in-excel/

If you are not familiar with VBA Code and how to use it this article may help:

http://www.contextures.com/xlvba01.html

Hope this helps

Matt