1.In the SharePoint online, if we share a folder with a Microsoft 365 group with the Share menu in the ribbon and choose "People in your organization" in the Link Settings, after the members of this group open the link of the shared folder in the email, the shared folder will show in their Shared with you section in the OneDrive.
(1)Open the folder in the email.
(2)The shared folder shows in their Shared with you section in the OneDrive.
2.Here are steps to apply permissions for a sub folder.
(1)Select the folder -> Manage access -> More options -> Advanced settings.
(2)Click Stop Inheriting Permissions -> Remove user permissions you do not need -> Grant user permissions you want.
(3)Then people with granted permissions only can access this folder.
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