This is more of a tedious thing than a difficult thing to do. You basically need to just store the items as 2 separate variables. So in your inventory “on clicked” events you would have to somehow link that to whatever means you “store” the item in that slot’s data and then use that data to set a new variable like “selected item #1” then do the same for the second clicked item, check if “item 1” is valid, if yes, “set item 2”, if not “set item 1” (this way you can determine if you already selected an item or not. And basically you just have to slowly logic your way through this. Just make it small baby steps and you’ll get there.