Read data from DataGrid

Hey guys,

I am reading data from an MS SQL database into a DataGrid.

What I'm trying to accomplish is to read the contents of a specific Column & Row from the DataGrid, after the information has populated from the SQL Server, and place it into a textbox or dropdown box.

What I've done so far is

   
    Private da As New SqlDataAdapter("SELECT * FROM Phone_Info", cs)
    Private ds As New DataSet
    Private cmb As New SqlCommandBuilder(da)

    Private Sub Form2_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        da.Fill(ds, "Phone_Info")
        dg.DataSource = ds.Tables("Phone_Info")
    End Sub

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        da.UpdateCommand = cmb.GetUpdateCommand
        da.Update(ds.Tables("Phone_Info"))
        
        ' The following 2 lines are where I believe the issue is at. I have tried changing these numbers around 
        ' and the only thing that happens is a return of "0". 
        PhoneName = dg.Columns(0).ToString 
        TextBox1.Text = PhoneName

        'I also tried this code with the same results.
        ' TextBox1.Text = (ds.Tables.IndexOf("PhoneName").ToString)

    End Sub

I have removed some of the useless code that shows the importing of data from the server.

I have scoured the internet looking for how to read the contents of a DataGrid and have found nothing that worked. I am eager to learn and if I could be pointed in the right direction that would be awesome.

Thanks!