Hello
I will be creating a 3rd person action rpg made in unreal engine. It will be 15-30 hours, have voice acting and animation, detailed open world, and characters. I don’t know unity. This game will be similar to the likes of SHenmue, Kingdom Hearts, FInal Fantasy, etc. It will not be quite as ambitious lol.
I don’t know how to program or use unity. This is an ambitious project. ANy reccomendations on how to learn unity? I AM IN NO RUSH BTW!!!
do you mean unity or UE4?
if you mean UE4 I would suggest taking a look at the documentation and the unreal engine youtube channel, I would also recommend taking a look at the samples you can download from the launcher.
hope that helps:)
My advice is to make a game design document for your game, if you haven’t already. You may not think you need it but it helps to have your ideas and plans for the game on paper.
Anyway, if you don’t know how to write code in C++ you’ll have a hard time getting your game from your awesome idea to playable reality. www.CPlusPlus is a great place to start learning about C++ programming. I taught myself how to program and learning to make games is the most fun way to learn how to code! 
Also, not to try and crush your dream, but if this is your first game ever I think you might be trying to go too big too fast. Start small and work your way up to a large project. I started with cloning Space Invaders and gradually worked my way up to FPS games!
If you need any help/advice I’ll be glad to give it.
Also make sure to take a look at the wiki: https://wiki.unrealengine/Main_Page + learning by doing -> so just start with something and try to find out how to get it to work