Hi @James Waweru ,
You can Create a new permission level from “View Only”(View Only permissions do not allow downloads) so that users can upload and edit files, but not download. Then grant custom permission levels to the subset of users you wish to block downloads.
Here are steps:
Step 1: Activate SharePoint Server Enterprise Features:
Step 2: Create a new permission level from “View Only”
Click “View Only” permission->Click “Copy Permission Level“ at the bottom of the page
Step 3: Assign the New Permission Level to Users you wish to block downloads
You can bulk Add Users from a CSV File to SharePoint Online Group using PowerShell or if the number is not large, you can manually grant permissions individually
For more detail information,please refer to: https://www.sharepointdiary.com/2020/10/sharepoint-online-allow-edit-permissions-but-not-download.html#ixzz7xVvxqIeL
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