I learned Lua for a game jam - during the course of the game jam itself. Like many, I found it a bit weird at first. 1-indexing feels wonky (you get used to it, though); now that I use Python all day, I would miss syntax shortcuts like list comprehensions going back to Lua.
When I was a kid, I learned C from a little pocket reference book while building little self-motivated projects. I still think this is the best way to learn - have a project in mind, and just enough fundamental examples to get you there.
I threw together the Lua tutorial mostly in one sitting, spending some time to edit, and going back and forth on how to keep the whole thing runnable while still explaining how external modules worked. Shortly after publication, Adam Bard contacted me with his idea for learnxinyminutes.com. I said great idea and ok'd the inclusion of the tutorial on Adam's site. Adam invited others to write their own similar-style tutorials, and his site grew up quickly.
Lua itself is a truly beautiful language, though I understand this is not a popular opinion. It's beautiful because you can learn the entire language, through and through, quickly. Memory and comprehension of the language itself get out of the way, so the only hard problems left are your decisions about what to do with the language. (You ask "How will I?" vs "How can I?") Instead of being feature rich through added features, it's feature rich through good language design. I expect some will disagree with me, but as one comparison point, consider the complete syntax of Lua:
https://www.lua.org/manual/5.1/manual.html#8
versus, say, Chapters 11-14 of the ECMAScript spec:
https://tc39.es/ecma262/#sec-ecmascript-language-lexical-gra...
It's not apples-to-apples - the ECMAScript spec is spelling things out in detail, while the Lua section is an overview - but it's still a thought-provoking contrast.