Hi @Danish Hakak ,
To apply a block download policy to a SharePoint Online (SPO) site, users need to have a SharePoint Advanced Management license. However, only SharePoint administrators need to have this license to execute it using PowerShell. For guest users, they do not have a SharePoint license and therefore are not affected by the blocking download policy. However, they will still be able to access the site and its content. If you want to restrict guest users from downloading and printing, you will need to use a different approach. So there is no need to spend money on SharePoint Advanced Management license.
You can set it to block download when sharing files.
Alternatively, create a new permission level and give external users permission so they can only view, not download.
Hope this is help.
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