if you want DRM-free, bandcamp is the best way, but for “exploring” subscribing to spotify is the best way in terms of quantity, and it doesn’t pay much less than other DRMs even if it has a monopoly, and is not from the USA or China
Here you can compare other services if you are interested in how much money goes to the creators: https://streamingcalculator.com/ or https://www.musicgateway.com/royalties-calculator
otherwise if you don’t want to pay, youtube + soundcloud with adblock is the best solution. or if you really have a lot of time you can make your own self-hosted pod on funkwhale: https://docs.funkwhale.audio/administrator/index.html
yes, but singleboard computers take up less space, make less noise and have almost non-existent energy consumption