@Kulbhushan_Kulbhusha
I have made such print formats.
If you can switch to laser printer and only water mark is stopping you, You can easily add water mark and Letter Head in Print Format.
ERPNext also provide feature to add footer and page number.
You can create such print format without writing any code.
Reference: https://frappe.github.io/erpnext/user/manual/en/setting-up/setup-wizard/step-5-letterhead-and-logo
https://frappe.github.io/erpnext/user/manual/en/setting-up/print/letter-head.html