Hi,
When you say you copied Notion from your laptop to your desktop that may be the issue. We would suggest (for troubleshooting) deleting it from your desktop system and installing it there in the normal way to see if it works as normal afterward and maybe downloading the installer again first and installing it again.
If it's not looking correct when you launch it that could indicate that some of the necessary files or folders are missing. If you continue to have issues, make sure that your desktop meets the minimum OS requirements for your version of Notion and make a support ticket so that a support rep can assist you in getting it running correctly.