If you want to try the Mac OS, well... come on over.
If you do buy a Mac, GET ONE WITH AN SSD INSIDE.
The OS "needs the speed" of an SSD to perform properly.
I believe there are still some iMacs being sold with platter-based hard drives inside, and these will be almost-unbearably SLOW.
If you already have a display, a USB keyboard and a USB mouse that you like, the 2018 Mac Mini might be a good choice. Just plug in the peripherals you already use.
Also, if you get a Mini, pay the $200 extra for 16gb of RAM (instead of 8).
It will run better, longer.
I'd buy the i5 Mini, but folks seem ok with the i3 version.
A 256gb SSD will get the job done, but you'll probably want external USB3 storage as well.
Same for the 512gb SSD.
My advice is DON'T pay Apple's high premium for the 1tb SSD -- not worth it (at least to me).
You can save a little $$$ by buying from Apple's online refurbished store. The items look like new, and come with the same 1-year warranty as new ones.