I need to remove all the photos from ipad its too full , i want to keep them in a newer ipad

If they’re on both devices already, then go into the settings on the old ipad and access the iCloud settings. Turn off photo syncing. THis means that any photo changes made on the old device will not be reflected on the new one. Then delete your old photos.

iF you don’t have any other copies of the photos, you may want to use Dropbox or some other cloud syncing service and upload the photos there, just to have an extra copy (in case something goes weird or wrong better to have an extra copy than lose your only copy)