Thing is, amateur radio is a really deep universe and there's almost no end to how much stuff you can learn or experiment with or try, so it takes a while to get a feel for things and know what you want out of it. You say you have a lot of hobbies - this can so easily be another one, a potentially massively-time-consuming one hahaha :)
Since you're probably intending just fairly short-range group<->group communication you probably want a typical handheld VHF radio. An "HT" as it's often called, or "handie-talkie". You can get cheap ones as low as like $50 but more often around $100. Baofeng makes the cheapest ones (I got one for $20), but they may not be legal to transmit with in your region, depends on where you're located. I only use one to listen for trucks on logging roads, or as a backup emergency radio. You won't really need digital modes like DMR or D-Star, in my opinion. In terms of how to use, the radios always come with comprehensive manuals that explain all the functions and how to use them. I learned everything I need to know to use my radio from the manual. You can probably buy one used, or scour some forums to know what the most reputable radio equipment vendors are. It's definitely a lot easier to get into this stuff if you know someone who's already into it, as everyone is into radio for different things. That said, ARRL has a decent "Get on the Air" site which you might find useful! Check it: http://www.arrl.org/get-on-the-air
Hope this helps a bit, even if it's just some general info... Can answer other questions if you have some. :)