
Hi @Krishna Moorthy ,
SharePoint Server: You can try turning on anonymous access. Users can access SharePoint content without validating their credentials. Anonymous authentication is disabled by default. You typically use anonymous authentication when you use SharePoint Server to publish content that doesn't require security and is available for all users, such as a public Internet website.
Reference: Manage anonymous access for a web application in SharePoint Server
How to Enable Anonymous Access in SharePoint 2013 / 2016
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SharePoint Online: Anonymous access is not supported in SPO sites from safety reasons and because sharing with external users is well done through Azure Active Directory(always required to authenticate the user against Azure Active Directory).
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