I guess it depends on what you do, but as an awerage user - not really much to learn in terms of Linux. No special knowledge needed to use it like a normal person. I had to reformat some drives so Linux can use them and learning about Heroic games launcher, Lutris and Bottles to run non-steam games and windows software amd learn about compatibility layer built into Steam.
Otherwise it just works. Using Linux Mint. Didn't boot to Windows pretty much since I installed it - there was no need.
Seconded. Linux Mint is really comfy and intuitive coming off of lifetime of Windows