Hi, Please tell me about how to up date my Mac Os 10.10.5 to OS which can support Window Os

What model / year of Mac do you have exactly?

What Windows version are you trying to install?

Are you trying to use Bootcamp? Or a Virtualization solution?

macOS 10.11 El Capitan or later support Windows 10 through Bootcamp.

How to get older versions of macOS

Link->How to get older versions of macOS - Apple Support