Ahmed,
You will have to add a section break on page ten. Go to Insert - break -
choose section break next page.
Now go to View - Header and footer - click on the last button of the toolbar
which brings you to the second section, click on the button same as previous
to disconnect your header from the first section. Click on the page number
button, click on the formatting page number button, next to start at choose
ten, close.
Luc