Hello AppleKim26!
We see you are having some trouble installing macOS Catalina and are getting an error creating a boot volume for the APFS install. We want to do all we can to help get that device updated so you can enjoy the latest features. Let's start with these steps:
First, you can attempt to repair the disk using Disk Utility to see if any issues are detected: Repair a disk using Disk Utility on Mac. You may need to select a different macOS version at the top of that page depending on what version you are currently on.
Second, you can try to install that macOS update using recovery mode: How to reinstall macOS from macOS Recovery. Specifically during this step you will want to restart and hold "Option-⌘-R" as that will then attempt to install the latest macOS compatible with your device.
We hope those steps get this issue resolved for you. Take care!