Hey there Lillian1917,
Thanks for reaching out to the Apple Support Communities. If you'er seeing bright or dark spots on your MacBook Air display, it is possible that this may indicate a possible issue with the display. Check out this link for more details: If your Mac display doesn’t look right - Apple Support
If you see bright or dark spots on a flat-panel or Mac notebook computer screen: Your display may have pixel anomalies. If you suspect your Apple display contains a high number of anomalies, take it to an Apple Authorized Service Provider.
Do the spots remain after restarting your device? If unsure give that a try with the steps shown here: Shut down or restart your Mac - Apple Support
Restart your Mac
- On your Mac, choose Apple menu 
> Restart.
If you don’t want app windows that are open to reopen when your Mac restarts, deselect “Reopen windows when logging back in.”
We'd also recommend testing the issue in safe mode. This can help to determine if the issue may be caused by some software that loads as your MacBooks starts up. For steps on how to boot into safe mode, and what to do if the issue doesn't occur in safe mode, check out this next link here: How to use safe mode on your Mac - Apple Support
Apple silicon
1. Shut down your Mac.
2. Turn on your Mac and continue to press and hold the power button until you see the startup options window.
3. Select your startup disk, then press and hold the Shift key while clicking “Continue in Safe Mode.”
4. Log in to your Mac. You might be asked to log in again
Keep us updated on the results, and we'll continue from there.
Best regards.
