I've learned what I know through just asking questions of the community, just like you have been, and watching all the YouTube videos I can get my hands on about meshtastic.
You might also run into another system called meshcore, and it's very similar to meshtastic, but at least I won't touch it, because it's not fully open source. The firmware for the devices is open source, but the application that you install on your phone to interact with it is not open source, and therefore I will not touch it.