Install macOS On Unsupported Macs

[EDLIU]

Can I use the steps listed below to install the macOS High Sierra on my old 2008 iMac(which does not support macOS High Sierra)?

How to Download a Full macOS High Sierra Installer App

How to Create a Bootable Install Drive for macOS High Sierra

Moreover, can I use the same way to install macOS Mojave or macOS Catalina on my old 2010 MacBook Pro?

Thanks.

 

[EDLIU]

macOS Catalina Patcher.

If I download and install the macOS Catalina on my unsupported MacBook Pro, will it work?

Thanks.