Lightroom Classic cache menu tab
Adobe Lightroom instructs you to go to preferences and select cache in order to designate a drive to store originals. There is no cache tab showing
MacBook Pro 13″, macOS 15.2
Make sure your hard disk has enough space (never let it get under 15% free). Turn off time machine, and all cloud backup options that might be running.
If that still fails, you can uninstall it, and reinstall it from Adobe Creative Cloud.
If the uninstall option does not exist, AppCleaner has an excellent facility to completely remove the software by simple drag and drop of the app over its window.