Transferring images to iPad

Are you using iTunes as the conduit through which you transfer the photos? See the section about syncing photos manually with iTunes here.

Keep your photos safely stored and up to date on all your devices - Apple Support

It really is very straightforward. If something is unclear, post back. Note that you can not sync photos if you are using iCloud Photo Library.

I don't know how many photos you have but an alternative way would be to simply e-mail them to yourself and save them from that email.

I Have a Windows computer but if I want to use iTunes I will make a folder of the photos I want on the device on the computer. What iTunes does is sync the content of a folder into the photos app on the iPad. The downside....anything you sync on must be synced off...as in removed from the folder then the iPad synced to allow iTunes to remove the photos. (Which has the downside of making synced photos undeletable, hence why I prefer e-mailing them to myself)

however, once you have the folder of photos on the computer, open iTunes and attach your iPad. Under the 'info' or 'summary' tab of itunes (just what it's called varies from iTunes version to iTunes version), if you scroll down you'll see the option to sync photos and to choose a folder. Do that and then sync. the photos should appear on your iPad.

To add on to this, you could always go to iCloud.com, upload the photos there, and then just enable The Photos Library under Settings -> iCloud. It will populate on your iPad at that point (in theory).

You have to place the photos into a folder that you can select in the Copy Photos from option in the PHotos tab in iTunes. Did you place the photos into a folder on your computer? How do you organize your photos?

It used to be that you would not Photos under the device unless you already had photos on the device. Perhaps that has changed. I have been syncing photos this for so many years now, I haven't checked to see if that has changed.