First datapack

I'm setting up my first server and I want to override Daily Quests loot tables so the items are RPG Coins instead. 
I followed the initial steps in Tutorial:Creating_a_data_pack, so I did the following: 
created the datapack folder in the correct world folder
created the pack.mcmeta folder 
verified that the datapack and its description show up when i use /datapack list in the server.
then i made the Data folder, then went to Daily Quests' Common folder to grab the source files for the loot tables. 
Now this is where I wasn't sure what I was doing. I tried copy pasting them and simply editing the values by replacing them with RPG Coins' item tags. 
That didn't work. 
So now I'm here!