Make file not moveable, copyable or deleteable?

[4x2y]

His code will grant the user modify access. How can I edit the code to my desires? And what does he mean with "MYDOMAIN\someuser"?

I modified like this to deny access to the specified file

Option Strict On
Option Explicit On
 
Imports System.Security.AccessControl
 
Public Class Form1
 
    Dim FilePath As String = "file\path" 'Specify the file here
    Dim UserAccount As String = "computer_name\user_name" 'Specify the user here
 
    Dim FileInfo As IO.FileInfo = New IO.FileInfo(FilePath)
    Dim FileAcl As New FileSecurity
 
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        FileAcl.AddAccessRule(New FileSystemAccessRule(UserAccount, FileSystemRights.Modify, InheritanceFlags.None, PropagationFlags.None, AccessControlType.Deny))
        'FileAcl.SetAccessRuleProtection(True, False) 'uncomment to remove existing permissions
        FileInfo.SetAccessControl(FileAcl)
    End Sub
 
End Class

Edit:
to know your computer name, open Control Panel> System> and see Computer name