Businesses (of all sizes) can use the Windows 7 ESU program to keep receiving security updates until Januari 2023.
I tried switching one of my customers to a Mac, because part of her workflow (graphics design, video editing, DTP) made her an ideal candidate. It was a horrible disaster, macOS is buggy in ways you often don't realize and limited in other ways that may really hinder people's work. I would caution anyone thinking of doing this.
