Hi @SeHor ,
1.What you see is one normal UI, the drives of each node are not included in the FCI UI. So you can not see it.However,You can see drives of each node as next screenshot shows:
2.Yes. You do. If you need one new requirement for one new disk to backup, you can add it as this : how-to-add-a-new-disk-to-an-existing-sql-server-failover-clustered-instance
BR,
Mia
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