You will need an AppleID account.
I tried unsuccessfully to create one of these using the App Store app on the mac1.metal instance. If you need a new AppleID for your project, go to https://appleid.apple.com/account to create one.
I also had big problems using the Apple App Store on the mac1.metal instance to download Xcode, so I recommend the following procedure.
Open Apple Music on the mac1.metal instance.
Open Safari on the mac1.metal instance and go to http://developer.apple.com/xcode.
Click the version of Xcode you want to download. If you need an older version, try this link and if needed filter by Xcode version number.
Sign in.