VOR/ILS navigation

Can someone explain to me how the whole VOR/OBS/CDI thing works? Say I want to fly from Gadsden (KGAD) to Huntsville (KHSV). How would I set it up and then how would I return?
Flight Simulator and other chat
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https://forums.simviation.com/phpBB3/viewtopic.php?f=20&t=56253
Appreciate the help. Actualy my boss (retired USAF Colonel that flew F-15s, A-10s and C-141s, Delta airlines 777 pilot, L-39 intructor) gave me an in depth lesson on navigation when I asked him a simple question about VOR. I got the whole VOR/Localizer/ILS/GPS lecture LOL