How to make the numbering on the master page above any image and design in all pages InDesign

Hi Ahmed, 
On the master page have you used the 'Current Page Number; Symbol in the text frame?
Type > Insert Special Character > Markers > Current Page Number

This will number each page in your document automatically. If you place this frame on a layer as @jmlevy explained at the top of the layer stack, this will display above any items on any page in the document. If you need to edit any page numbers or style them on a specific page, select the page in the pages panel, right click on that page and select 'override all master page items'. This will then allow you to edit any of the items on that specific page that you have created on your master page but will not change anything on other pages of your document. 

Refer to this help page.

https://helpx.adobe.com/uk/indesign/how-to/override-master-pages.html

I hope this solves your problem.