New Xbox console - how to download a previously purchased game

Hello the game should give an option to restore previously purchased items.

Hello JB!

Thanks for the replies. Can you confirm that you are able to go to your
Microsoft Account Order history and find the transaction for the purchase of Fortnite: Save the World Standard Founders Pack? If you can see it try clicking the image of the purchase or the little square to the top right of its image and it should pull
it up from the store and see the items status. If you are unable to locate the transaction from going all the way back in your Order History you will need to sign onto the account that completed the transaction.

Thanks!

We don't have an Epic Games Account (purchased it through the Microsft Store). But I will contact Epic about it, thank you.

If you're logged into the account that purchased the game go to My Games and Apps and highlight the game. Press the menu button and go to Manage Game. From there you should be able to see any DLC you have downloaded or any DLC that you have ready to install.
Choose what you want to download and you should be good to go.

If you haven't downloaded the game itself yet, start with that under My Games and Apps and go to your Ready to Install list. The game will be listed there.

Or if you go to the Store, since you already own the game, it should give you the option to install from there.

Log in with the same account as you purchased the game with and you should be able to download it.