C# - List<> link id to name

I got this application that reads the employee data from the database, only problem the boss of an employee is set in employee_id and not in name, which is what I am looking for.

I got a List filled with all the employees. So I am looking for a way to query it with LINQ through the list to link the employee_id to the Firstname/Lastname.

Example: The employee with the ID 1 is Nancy and her boss is Andrew, but it doesn't say Andrew it says 2. But it should say Andrew

I also added 2 images below to add to my explanation.

Listview of the employees

Reading out the list of employees into the ListView