About the print page size

Or will the page scales to the size of page that entering to the printer?

In most cases it will scale just fine, so no need to do anything. Are you looking for something special? ??

CSS has some support for print though. If you want some more control on pagesize and know how to add your own CSS, this article might be wordt a read:https://www.smashingmagazine.com/2015/01/designing-for-print-with-css/