How to refresh or show immediately in datagridview after inserting?

Try refreshing the datagrid after each insert

datagridview1.update();
datagridview1.refresh();  

Hope this helps you!

Only need to fill datagrid again like this:

this.XXXTableAdapter.Fill(this.DataSet.XXX);

If you use automaticlly connect from dataGridView this code create automaticlly in Form_Load()

Use LoadPatientRecords() after a successful insertion.

Try the below code

private void btnSubmit_Click(object sender, EventArgs e)
{
        if (btnSubmit.Text == "Clear")
        {
            btnSubmit.Text = "Submit";

            txtpFirstName.Focus();
        }
        else
        {
           btnSubmit.Text = "Clear";
           int result = AddPatientRecord();
           if (result > 0)
           {
               MessageBox.Show("Insert Successful");

               LoadPatientRecords();
           }
           else
               MessageBox.Show("Insert Fail");
         }
}

You can set the datagridview DataSource to null and rebind it again.

private void button1_Click(object sender, EventArgs e)
{
    myAccesscon.ConnectionString = connectionString;

    dataGridView.DataSource = null;
    dataGridView.Update();
    dataGridView.Refresh();
    OleDbCommand cmd = new OleDbCommand(sql, myAccesscon);
    myAccesscon.Open();
    cmd.CommandType = CommandType.Text;
    OleDbDataAdapter da = new OleDbDataAdapter(cmd);
    DataTable bookings = new DataTable();
    da.Fill(bookings);
    dataGridView.DataSource = bookings;
    myAccesscon.Close();
}