It ranges in price, but for most people Windows 10 Home ( buy in the US or in the UK) is the version to go for, although there are some good deals on Windows 10 Pro at the moment as you can see below. If you didn't take that offer up, or perhaps weren't able to due to a work security lockdown then you now have to pay for the upgrade. There was a period at the beginning of Windows 10's life - note, there's no Windows 9 to worry about here, it never existed - when it was offered as a free upgrade (until 16 July 2016, so quite a while back!).
Otherwise it's business as usual - as outdated as said business is. You just won't receive any more security updates. Here's what the plug-pull of the older operating system means.
So if you're still running the decade-old operating system you won't be getting any more updates, bug fixes and so forth. (Pocket-lint) - The end of an era: Microsoft ceased to support Windows 7 on 14 January 2020.
