How to assign a permission?

Hi Good morning to all,
I am developing one web application.
In this Web Application, three different roles exists.
01. Admin
02. Fleet-Admin, there can be more number of Fleet Admins.
03. Fleet-User, there can be more number of Fleet Users.
Admin can grant permission for one Fleet-Admin to view one another Fleet-Admin information.
How can i implement this feature in asp.net?
Thanks in advance.
Regards,
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