First, note that this is Apple Support Communities, not Apple Support. “We” are users like you and have no power to fix anything. All we can do is suggest troubleshooting you can perform.
To get help from Apple, contact them: Official Apple Support
For your issue, first ensure that your Spotlight settings are showing Apps.
- Open System Settings
- Click on Spotlight
- Scroll down to the Results from System section
- Ensure that Apps is toggled on

More info from Apple: Select result categories for Spotlight on Mac - Apple Support
If the above is set correctly, then you need to rebuild your Spotlight index:
Rebuild the Spotlight index on your Mac - Apple Support
If that doesn’t work, Copy/Paste this into Terminal. sudo will ask for your password. Just type the password and hit return. It won't show anything on screen. Those two commands essentially nuke all the Spotlight records then force a reindex. You may need to restart or log out/in after running the commands.
sudo mdutil -X /; sudo mdutil -i on /
Spotlight re-indexes your Mac after a macOS update, and this process can take some time.
About Spotlight indexing and search results on Apple devices - Apple Support