I'm Wanting a Datapack and Need Help making one! Plz

Mk so. I am Completely New to making datapacks. I've not even poked them with a stick yet! This Month, I did a little test with ChatGPT to see if it could make datapacks to what I was wanting and well, it can't make datapacks from what I've recently seen. 
Also this month, I joined a roleplay server called Complex Creations! A origins server that allows it's players to make data packs and use them with they're characters! My issue is, I have No idea how to make datapacks. No idea on where to start, where to finish the code, or even how to Write the code cause, I've never done that either! I've never written code before
But for the datapack itself, I was wanting a Witch Origin made so I can make the skin for my character. I'm not even sure if there's a way to make a 1:1 recreation of how a witch acts with a datapack but, Hey! It's why I'm making this post right?
I'll give a cookie to who all helps me 😄