How to make a GUI that pops up when i click on an entity

So i have this project where I wanna make an entity thats clickable and when i click on it a GUI appears but i cant do the coding and i dunno why. (I use 2024.4 cuz the geckolib) So made a "right click trigger procedure" but its not working with the "Open GUI <my gui> for [Event/target entity] pass location x: [x] y: [y] z: [z]"