How to run DB Admin Tool (GUI) in IBM DB2 Express-C?
DB2 Express-C version 10 and later no longer include a full suite of administration tools as part of the installer (the "Administration Tools" you installed might only include the ones you're looking at...).

Like MySQL and SQL Server, the administration tools are now available as a separate download.

The official tool you're looking for is IBM Data Studio, which is available free of charge.

Older versions of DB2 Express-C used to include the legacy Control Center apps, but IBM has deprecated those and is really pushing the Eclipse-based Data Studio.