When you play, you'll collect items, and sometimes these items can be stacked together. This means you can have multiple of the same thing in just one spot in your inventory. For example, you might have 12 carrots in one slot or 30 Shiny Gemstones in another. There might be times when you want or need to take just one item out of a stack before you use it. Here's how you do that:
On a computer: Press and hold down the SHIFT key on your keyboard. While holding SHIFT, click on the stack of items you want to separate and drag one of them to an empty spot in your inventory. This will leave the rest of the stack where it was.
On a phone or tablet: This can be a little bit tricky, but it's still possible! Tap and hold your finger on the icon that shows the stacked items. Keep holding it down for a moment. You should see one item separate from the rest of the stack, and then you can drag that single item to a different empty spot.