Did you select the photos and delete them? If so, they remain in the trash for 30 days. You can find the Recently Deleted photos album on in your Mac Photos app in the sidebar in newer versions, and in your list of albums in older versions. Or, you can do it at iCloud.com. On your Mac, use your web browser and go to iCloud.com. Log in to your iCloud account. Go to the Photos app inside the web site. Then look for the Recently Deleted album.
Either way, you'll find your photos in there and you can select and recover them.
Did you select the photos and delete them? If so, they remain in the trash for 30 days. You can find the Recently Deleted photos album on in your Mac Photos app in the sidebar in newer versions, and in your list of albums in older versions. Or, you can do it at iCloud.com. On your Mac, use your web browser and go to iCloud.com. Log in to your iCloud account. Go to the Photos app inside the web site. Then look for the Recently Deleted album.
Either way, you'll find your photos in there and you can select and recover them.