how to create username and password provided that with SQL server

//Add this namespace
using System.Data.Sqlclient;

oledbconnection con;
oledbdatareader dr;
oledbcommand cmd;

//We need to write the connection string
con=new sqlconnection ("Data Source=  ;Integrated Security=   ;User Id=  ; Pwd=  '");
//Now rightclick the button and write the below coding
{
con.Open();
cmd = new SqlCommand("SELECT UserName ,pwd FROM [aaa] WHERE UserName='" + textBox1.Text + "' AND pwd='" + textBox2.Text + "'", con);
SqlDataReader dr = cmd.ExecuteReader();
string userText = textBox1.Text;
string passText = textBox2.Text;
if (dr.Read())
{

this.Hide();
ddd mp = new ddd();
mp.Show();
dr.Close();
con.Close();
}
}