Editing Existing Sites Permissions
On your SharePoint homepage, click the gear icon located in the upper right corner, then select 'Site contents':
Locate the site you want to modify permissions for in the list. Hover over the site to highlight it, then click on the three dots (⋮) and select 'Settings':
This will take you to your site's settings overview. From there, navigate to 'Permissions for this document library':
To make the permissions unique, click 'Stop Inheriting Permissions' and 'OK' from the pop-up:
From here, you can start to customise permissions. Click on 'Grant Permissions' to continue:
This will open a dialog box where you can specify who will be given permissions. You can enter either an individual or a group. To avoid sending an invitation, uncheck 'Send an email invitation'. Then, set the desired permission level. Make sure you click 'Share' once done:
This is shown once the page is refreshed:
If you want to prevent your visitors from seeing the page, select them and click 'Remove User Permissions' and 'OK' from the pop-up:
