You say you have 3rb of storage? Do you have a subscription to the Photographers plan??
If so then log in to your Adobe a/c from Lightroom on your iPad and then all the original files you have imported into Lightroom will be uploaded to your cloud storage and to your computer if you have Lightroom Classic installed there.
Regards, Denis: System iMac mid-2015, 5K 27” monitor, macOS10.15.3: Lightroom Classic 9.2, Photoshop, Camera OM-D E-M1.