I can't give you advice on business accounts. I have Microsoft 365 Family.
You can't add a shared folder to quick access until you first add the shared folder to your OneDrive. It has to download to your computer as an available file or as a File On-Demand cloud file.
https://support.microsoft.com/en-us/windows/pin-remove-and-customize-in-quick-access
By default, File Explorer opens to Quick Access. You can set a folder to show up in Quick access so it'll be easy to find. Just right-click it and select Pin to Quick access. Unpin it when you don’t need it there
https://www.digitalcitizen.life/how-view-pin-unpin-items-quick-access-section-file-explorer-windows-10/
Add shared folders to your OneDrive:
