Thank you for reaching out to our Q&A forum.
Based on the information you described, I understand that you have multiple pages, each containing Quick Links and an Advanced Search web part that points to a specific folder within a document library. Your goal is to grant access so that each group can only access its own page and related library/folder and cannot see the main site page that lists all pages.
After testing this in my environment, this scenario is possible in SharePoint Server 2019, as it still supports permission inheritance and unique permissions at both the page and library level.
-You can assign permissions to individual pages so that only specific groups can access them:
Go to Site Contents > Open the Site Pages library > Locate the page you want to restrict > Click the three dots (Show actions) > More > Properties > Select Shared with > Advanced > Click Stop inheriting permissions > Grant permissions to the appropriate SharePoint group > Remove any groups that should not have access > This ensures each group can only access its own page and no other pages.
-You can apply the same concept to document libraries or specific folders:
Go to Site Contents > Open the target Document Library > Click Settings > Select Permissions for this document library > Click Stop inheriting permissions > Grant access only to the required group (If needed, this can also be done at the folder level inside the library.)
-To stop certain groups from seeing the main site page:
Go to Site Settings > Open Site permissions >Remove those groups from Site Visitors and Site Members > Grant permissions only at the individual page or library level, as described above
I hope this helps clarify the setup. If you need guidance on best practices or permission design to avoid maintenance issues, feel free to let me know.
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