how do i find photos on i cloud from 1995. i can only find photos back to 2020

See the article Back up your Mac with Time Machine - Apple Support

• Time Machine automatically makes hourly backups for the past 24 hours, daily backups for the past month, and weekly backups for all previous months. The oldest backups are deleted when your backup disk is full. The first backup might take a long time, but you can continue using your Mac while a backup is underway. Time Machine backs up only the files that changed since the previous backup, so future backups will be faster. 

See Recover files using Time Machine and Spotlight on Mac - Apple Support

If I never set up a back up, then even if I set one up now I won’t be able to retrieve 1995 photos. Is that correct? - very true .

The only back up I set up was I cloud. I thought That saved everything. I was wrong? - no you were not wrong .

See the article Other ways to back up and restore files - Apple Support

Use cloud-based services

Cloud-based services don't require you to connect an external hard drive to your Mac. For example, iCloudcan automatically store your photos, calendars, contacts, notes, passwords, and more. And it includes iCloud Drive, which can store documents, desktop files, and other files of your choosing. To access those files, you just need to be signed in to iCloud. Other cloud-based services are available from third parties.

iCloud Photos is only saving the current state of your Photos Library. To recover photos you have deleted permanently, that are no longer in the Recently Deleted folder, you have to use your backups you made, for example Time Machine backups on a Mac.

See the article View photos in the Photos app on iPhone - Apple Support

Using only an iPhone time machine can't be set .