I ran internet recovery on my 27" iMac (2014). How do I re-install OS X without updating all the way to Mojave?

I ran internet recovery and it formatted the iMac I'm using back to 10.10.5 Yosemite. I was fully updated to Mojave prior to updating. But I don't want to update to Mojave because it wouldn't let me Bootcamp to Windows properly. I don't know if it'll work now but given I'm back at Yosemite, I might as well test it out on High Sierra etc.

• I looked on the Apple Support download page but almost all of them said they didn't run on the computer. So I didn't want to download and run a ton them.