How to take a split snapshot of an Ubuntu hard drive?

Question

linux

Good afternoon
There are 2 hard drives: 320 GB and 1 TB (encrypted, only make a copy sector by sector)
Two questions:
1. In the case of 320 TB, there is enough space on the disk for a copy. How to make a copy (even the same dd) with splitting (1.4 GB)? And how then to recover? (copy of a non-system disk)
2. In the case of a 1 TB disk, there is not enough disk space for copying. How to make a copy in parts and also with a breakdown into parts?