Can someone help me create a simple inventory?

I am making a game using the rolling template and need to have an inventory system that keeps track of 3 types of collectibles. I would like to be able to have the 3 amounts displayed when I press a key at the top of the screen. I would also like to be able to press a key to bring up a page with the totals for each level.

Basic Item System with stacking functionality - Please Critique! - Blueprint Visual Scripting - Unreal Engine Forums!

This should get you started