Backup btrfs storage pool, and delete it

Hello, i been reading the docs on how to do a full back up, i was wondering if someone can provide an example, am using btrfs subvolum, as my default storage.
In case i wish to make weekly full backups to third part cloud storage, and had to re install my system and import the back-up, how will i proceed? Thanks in advance.

I did a full back-up with same ownership of all files and directories of
/var/snap/lxd/common/lxd and my-btrfs-subvlm
after removing lxd, re installing it, removing the files and directories on the previous paths, and extracting the tar’s with same ownership flag, the old containers run again, but i fail to run new containers, with error.
Error: Failed container creation: Create container from image: Failed to create image volume: UNIQUE constraint failed: storage_volumes.storage_pool_id, storage_volumes.node_id, storage_volumes.project_id,, storage_volumes.type
Where did i go wrong about this please?