how to add admin and user in a query

try
            {
                SqlConnection con = new SqlConnection(@"Data Source=LENOVO-41B3F2CE\SQLEXPRESS;Initial Catalog=IMS;Integrated Security=True;Pooling=False");
                string query = "SELECT [user].* FROM [user] where u_name='" + txtusername.Text + "' and pwd='" + txtpassword.Text + "'";
                SqlCommand com = new SqlCommand(query, con);
                con.Open();
                if (com.ExecuteReader().HasRows)
                {
                    //if ((txtusername.Text = "admin") && (txtpassword.Text = "admin"))
                    {
                        Response.Redirect("allinventory.aspx");
                        Label3.Text = "successfully";


                    }
                }
                else
                {
                    Label3.Text = "not successfully";
                    txtusername.Text = "";
                    txtpassword.Text = "";
                }
                con.Close();
            }
            catch (Exception ex)
            {
                Console.Write("" + ex.Message);
            }