Seperate UI Texture From Model Texture

Hey there! I know this same post has been made several times, but I've only ever found solutions for Neoforge that commentors said didn't work.

So, I want to apply a 2D texture that appears in the GUI to a 3D model Geckolib animated item on 2024.4 1.21.5. If you have some kind of Json solution or anything, it would be much appreciated!