When I Copy The Any Url Of My Application Its Running Without Login How To Control It.

Actually this is my code how to check the user authenticated or not
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click

Try
Dim con As New SqlConnection(ConfigurationManager.ConnectionStrings("SqlDbConnection").ToString())
Dim command As New SqlCommand("cyl_user_login", con)
command.CommandType = CommandType.StoredProcedure
command.Parameters.Add("@emp_code", SqlDbType.VarChar).Value = txtusername.Text.Trim()
command.Parameters.Add("@user_password", SqlDbType.VarChar).Value = txtpassword.Text.Trim()
con.Open()
command.ExecuteNonQuery()
Session("@emp_code") = txtusername.Text
'Session("user_password") = txtpassword
Response.Redirect("Home.aspx")
con.Close()
Catch ex As Exception
'Label1.Text = "Wrong Password"
'Console.WriteLine("SQL Error" & ex.Message.ToString())
Label1.Text = ex.Message.ToString()
'ScriptManager.RegisterClientScriptBlock(Me, Me.[GetType](), "alertMessage", "alert('" & ex.Message.ToString() & "')", True)
End Try

End Sub

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Label1.Text = ""
End Sub

Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click

txtusername.Text = ""
txtpassword.Text = ""
End Sub
End Class

Is that step really so complicated? Did you just copy the code without understanding it?
Look at
Session("@emp_code")
if that does not exist or is empty, then send the user back to login.

What you saying I am. Not understandable please find the solution