Users not being able to see other users uploaded file in SharePoint document library.

Hi hritik450, in lists, there is a setting available in the UI to show only items created by a user.

Unfortunately, in libraries, this option is not visible in the UI, but you can set it using for example a PnP PowerShell command:

Set-PnPList -Identity "Documents" -ReadSecurity AllUsersReadAccessOnItemsTheyCreate

Then users will see only documents created by them.

For changing the permissions of the items, you can use the approach defined here -> https://learn.microsoft.com/en-us/sharepoint/dev/business-apps/power-automate/guidance/manage-list-item-file-permissions

I hope this information helps.