Where to find the terminal for gift items in Splatoon 3

destructoid.com:

The Splatoon 3 terminal is an easily overlooked menu that you otherwise never really have to interact with, but it can be crucial for a few select things. One of them is picking up periodic rewards.

Head to the lobby room (where you can queue for turf war and ranked), and interact with the terminal/PC right there. That’s it! The game doesn’t explicitly tell you where the terminal is, so it might take you a while to locate it.

So one core use of this is to pick up gifts after the campaign. By finishing the main story quest (and defeating the final boss) you’ll instantly get access to a few cosmetics and the main weapon from the campaign. You can pick those up at the terminal.

You might also locate some objects, like bonus tickets, locker items, or Tableturf Battle (card game) packs in the campaign. If you’ve just come back from a story session and happen to be in the lobby, head to the terminal and double-check to see if you have anything. Just click the gift box icon and a pop-up will show you what you “Found in Alterna.”