Gamepad navigation for inventory UI

For my project I need the functionality that allows a gamepad to navigate and use menu systems within the game, for example I have an inventory UI that looks like this

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all of the inventory slots are custom widgets and the rest are default buttons arranged within a uniform grid panel, on begin play the inventory slots are added to an array so they can be accessed by other systems.

my question is how do I set up the blueprints to allow a gamepad to navigate this UI and possibly others in my game?

Take a look at these links: