If you truly have a Lightroom Classic subscription, then you can easily reinstall the latest version of Lightroom Classic using the Creative Cloud app
But you also refer to "LR CC", which may indicate you have an earlier version of Lightroom. You can't (easily) reinstall LR 6 or earlier on Mac OS 10.15 because the installers are 32-bit. (Adobe's overpaid marketers have created massive confusion with their renaming of the Lightroom family of products.)
So do Help > System Info and verify the exact version of LR you currently have.