Whats the best way to understand modding.

Im an MR 24 player and I've played on and off for years. I can't even do solo star chart, arbi, etc. I know people say anything is viable with the right build and I dont want to be stuck playing "meta" because it's boring at times. My builds both frames and weapons are terrible since i never really took the time to understand them. Whats the best way to learn modding? Trial and error, asking people for builds, watching videos(is there a video breaking down modding? Multiplicative v additive, elemental bonuses, faction mods, set bonuses, redundant mod pairs, etc)