Don't forget to do a full backup first to avoid problems..... having upgraded a few computers now. Its best to perform a full backup of your system.
We have already encountered bugs such as not enough space to upgrade and missing apple dock after upgrading .. Where customers computer have had to be restored or put in recovery mode to fix issues..
macOS Catalina gives you more of everything you love about Mac. Experience music, TV and podcasts in three all-new Mac apps. Enjoy your favourite iPad apps, now on your Mac. Extend your workspace and expand your creativity with iPad and Apple Pencil. And discover smart new features in the apps you use every day. Now you can take everything you do above and beyond.