Hello sydneyO7,
Thank you for reaching out to Apple Support Communities.
Were you syncing your photos with iCloud? If so, let's check the iCloud website to see if they are visible:
"View your photos and videos
- In Photos on iCloud.com, do one of the following:
- Click Library in the sidebar to see thumbnails of all your photos and videos.
- If you don’t see the sidebar, click
. - Click an album or folder in the sidebar to view its contents.
2.To change the size of the thumbnails, use the slider in the Photos toolbar.
3.To view a photo or video full screen, double-click a thumbnail.While viewing a photo full screen, you can click the thumbnails at the bottom of the window to see other photos. You can also press the arrow keys to move to other photos.
See also View your iCloud Shared Photo Library on iCloud.com."
More details can be found here: View your photos and videos on iCloud.com
If you are unable to find your photos, can you provide a few more details? Do you have a Time Machine backup of your computer? If so, when was the last time you backed up your Mac? Also, are all of your photos missing or just certain photos?
Cheers!