Hi,
unfortunately, it is not entirely clear to me what problem you are describing.
if you mean the xcode playground, which is empty so that you can get started yourself, then you can first go to the gallery via the learn button and then scroll all the way down and all the way to the right, where you will find the playground.
BTW: Swift Playground is attached to iCloud Drive, so accessible via iPad as well. maybe you find your codebases still there laying around in the iCloud Folder?