Hi @Kaberia David ,
Welcome to our forum!
As i know, we can move folders within one mailbox but not between two mailboxes in New Outlook for Windows. I notice that you want to move a folder to the shared mailbox, as a workaround, you can create a same folder in the shared mailbox, then press Ctrl+A to select all emails in the original folder and drag them to the same folder in shared mailbox.
Hope to help you!
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