Set data binding position through item selected in Data Grid View

SqlConnection con = Global.Con;
            con.Open();
            da = new SqlDataAdapter("SELECT * FROM Customer", con);
            mcb = new SqlCommandBuilder(da);

            da.Fill(ds, "Customer");

            txtCustomerFName.DataBindings.Add(new Binding("Text", ds.Tables["Customer"], "Cus_FName"));
            txtCustomerLName.DataBindings.Add(new Binding("Text", ds.Tables["Customer"], "Cus_LName"));
            txtCustomerAddress.DataBindings.Add(new Binding("Text", ds.Tables["Customer"], "Cus_Address"));
            txtCustomerEmail.DataBindings.Add(new Binding("Text", ds.Tables["Customer"], "Cus_Email"));
            txtCustomerRegDate.DataBindings.Add(new Binding("Value", ds.Tables["Customer"], "Reg_Date"));
            txtCustomerLoyalty.DataBindings.Add(new Binding("Text", ds.Tables["Customer"], "Loyalty"));
    
           bm = this.BindingContext[ds.Tables["Customer"]];

private void cmdBack_Click(object sender, EventArgs e)
        {
            

            if (bm.Position == 0)
                MessageBox.Show("Reached beginning of list!", "Cannot go further!", MessageBoxButtons.OK, MessageBoxIcon.Information);
            else
                bm.Position -= 1;
            
        }

        private void cmdNext_Click(object sender, EventArgs e)
        {
            
           
            if (bm.Position == (bm.Count - 1))
                MessageBox.Show("Reached end of list!", "Cannot go further!", MessageBoxButtons.OK, MessageBoxIcon.Information);
            else
            bm.Position += 1;
        }

private void CustomerSearch_Load(object sender, EventArgs e)
        {

            SqlConnection con = Global.Con;
            SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM Customer", con);
            da.Fill(ds, "Customer");
            dv.Table = ds.Tables[0];


            DGV1.DataSource = dv;



            
            
            


        }

        private void txtSearchString_TextChanged(object sender, EventArgs e)
        {

            dv.RowFilter = "Cus_FName LIKE '*" + txtSearchString.Text + "*' OR Cus_LName LIKE '*" + txtSearchString.Text+ "*' OR Cus_Address LIKE '*" + txtSearchString.Text + "*' OR Cus_Email LIKE '*" + txtSearchString.Text + "*'";



        }