Unfortunately, you are going to have to reinstall. The option to add the GUI to server core is not available in WS2022.
Server Core vs Server with Desktop Experience install options | Microsoft Learn
"Note
Unlike some previous releases of Windows Server, you cannot convert between Server Core and Server with Desktop Experience after installation. You will need to do a clean installation if you install later decide to use a different option."
Upgrade to convert is also not supported.
Upgrade and conversion options for Windows Server | Microsoft Learn
- Upgrades that switch from a Server Core installation to a Server with Desktop Experience installation (or vice versa) are not supported.