Hi, I've been working on Minecraft textures for a while, I've just never actually tried used them in Minecraft until now.
I followed the tutorial below, putting a few textures I made into the new folder the guy in the video said to put them in to see if it worked, but the pack doesn't show up in the resource pack list in Minecraft.
So how DO I put my resource pack in the "resourcepacks" folder and have it show up in-game? Could I just have done something wrong or is it done a different way?
Oof. That guy takes a LOT of unnecessary steps and gives a fair amount of advice that's really bad practice. Like editing the default files, which is a TERRIBLE thing to tell people to do even as a test. Just... make a texture that's all black or something! C'mon!
But with that said if you followed those instructions to the letter you should indeed have a fully functioning resource pack. He may have taken extra steps, but he got there in the end and nothing has changed in 1.14 that would be so radically different as to make any of that invalid. So it's very likely that you just made a mistake somewhere. He does give a short troubleshooting section at the end that you might want to re-watch.
He says to use a text editor called ATOM to make the pack.mcmeta document, but he doesn't really clarify why. Can I just use notepad?
I personally suggest Notepad++ if you're on Windows, or Gedit if you're on just about anything else. Both are freeware.
Whatever you use, you'll want to set the encoding to "UTF-8 Without BOM". The reason for this is that Minecraft doesn't always read .mcmeta files correctly if they're not encoded the way that it wants them to be. I'm guessing ATOM saves in "UTF-8 Without BOM" automatically... though I've no experience with it to confirm this.
I recommend not using Notepad, though if you know how to change the encoding when you save then there's no technical reason why you can't use it. It's just easier to use Notepad++.