Datagridview to database access

Question

hi,  I need help whenever I run my project there's a message saying "cannot find column 5" thanks! 
form 1 
contains:
datagridview(dgv1)  linked to database access
btnNew- allows me to add data in my datagridview
btnEdit- allows me to edit data in my datagridview
btnDelete - to delete
syntax:
Imports System.Data.OleDb
Public Class frmMain
    Public rows As Integer
    Public key As String
    Public num As Integer
    Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        conn()
        loading()
    End Sub
    Public Sub loading()
        com = New OleDbCommand("SELECT * FROM Products", con)
        da = New OleDbDataAdapter(com)
        ds = New DataSet()
        da.Fill(ds, "Employees")
        For num = 0 To ds.Tables("Employees").Rows.Count - 1
            dgv1.Rows.Add(ds.Tables("Employees").Rows(num).Item(0).ToString, ds.Tables("Employees").Rows(key).Item(1).ToString, ds.Tables("Employees").Rows(key).Item(2).ToString, ds.Tables("Employees").Rows(key).Item(3).ToString,
ds.Tables("Employees").Rows(key).Item(4).ToString, ds.Tables("Employees").Rows(key).Item(5).ToString, ds.Tables("Employees").Rows(key).Item(6).ToString)
        Next
        dgv1.Sort(dgv1.Columns(0), System.ComponentModel.ListSortDirection.Ascending)
    End Sub
    Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
        Form2.txtID.Text = dgv1.Rows(rows).Cells(0).Value
        Form2.txtLast.Text = dgv1.Rows(rows).Cells(1).Value
        Form2.txtFirst.Text = dgv1.Rows(rows).Cells(2).Value
        Form2.txtTitle.Text = dgv1.Rows(rows).Cells(3).Value
        Form2.txtCourt.Text = dgv1.Rows(rows).Cells(4).Value
        Form2.txtUsername.Text = dgv1.Rows(rows).Cells(5).Value
        Form2.txtPassword.Text = dgv1.Rows(rows).Cells(6).Value
        key = "Edit"
        Form2.btnSave.Text = "Update Changes"
        Form2.Show()
        Me.Hide()
    End Sub
    Private Sub dgv1_CellContentClick(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles dgv1.CellContentClick
        rows = dgv1.CurrentRow.Index
    End Sub
    Private Sub btnDelete_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDelete.Click
        If MsgBox("Are you sure?", MsgBoxStyle.YesNo) = MsgBoxResult.Yes Then
            com = New OleDbCommand("DELETE * FROM Products WHERE ProductID = '" & dgv1.CurrentRow.Cells(0).Value.ToString & "'", con)
            con.Open()
            com.ExecuteNonQuery()
            con.Close()
            dgv1.Rows.Clear()
            loading()
            MsgBox("Okay")
        End If
    End Sub
    Private Sub btnNew_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNew.Click
        key = "Add"
        Form2.btnSave.Text = "Add Item"
        Form2.Show()
        Me.Hide()
    End Sub
End Class
FORM 2
contains
txtID
txtLast
txtFirst
txtTitle
txtCourt
txtUsername
txtPassword
btnSave - allows me to save changes from editing my data and adding data
synatx:
Imports System.Data.OleDb
Public Class Form2
    Dim final As Boolean
    Private Sub Form2_FormClosed(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed
        frmMain.Show()
    End Sub
    Private Sub Form2_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        If final = True Then
            e.Cancel = True
        Else
            Dim res As MsgBoxResult = MsgBox("This will IGNORE CHANGES... Are you sure?", MsgBoxStyle.YesNo)
            If res = MsgBoxResult.No Then
                e.Cancel = True
            End If
        End If
    End Sub
    Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
        Select Case frmMain.key
            Case "Edit"
                com = New OleDbCommand("UPDATE Products SET EmployeeID = '" & txtID.Text & "', LastName = '" & txtLast.Text & "', FirstName = '" & txtFirst.Text &
"', Title = '" & txtTitle.Text & "', TitleOfCourtesy = '" & txtCourt.Text & "', Username = '" & txtUsername.Text & "', Password = '" & txtPassword.Text & "' WHERE EmployeeID = '"
& txtID.Text & "'", con)
                con.Open()
                com.ExecuteNonQuery()
                MsgBox("OK")
                con.Close()
                frmMain.dgv1.Rows.Clear()
                frmMain.loading()
                final = True
                Me.Close()
            Case "Add"
                con.Open()
                com = New OleDbCommand("INSERT INTO Employees(EmployeeID, LastName, FirstName, Title, TitleOfCourtesy, Username, Password) VALUES(@Column1, @Column2, @Column3, @Column4, @Column5, @Column6, @column7)",
con)
                com.Parameters.Add(New OleDbParameter("@Column1", txtID.Text))
                com.Parameters.Add(New OleDbParameter("@Column2", txtLast.Text))
                com.Parameters.Add(New OleDbParameter("@Column3", txtFirst.Text))
                com.Parameters.Add(New OleDbParameter("@Column4", txtTitle.Text))
                com.Parameters.Add(New OleDbParameter("@Column5", txtCourt.Text))
                com.Parameters.Add(New OleDbParameter("@Column6", txtUsername.Text))
                com.Parameters.Add(New OleDbParameter("@Column7", txtPassword.Text))
                com.ExecuteNonQuery()
                con.Close()
                MsgBox("Okay")
                frmMain.dgv1.Rows.Clear()
                frmMain.loading()
                final = True
                Me.Close()
        End Select
    End Sub
End Class
MODULE1- contains my other variables
Imports System.Data.OleDb
Module Module1
    Public con As OleDbConnection
    Public com As OleDbCommand
    Public cb As OleDbCommandBuilder
    Public da As OleDbDataAdapter
    Public ds As DataSet
    Public sql As String
    Public EmployeeID As Integer
    Public Sub Conn()
        con = New OleDbConnection
        con.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source= D:\nica\IT.mdb"
    End Sub
End Module

Answer 1

Dani,
There is a lot wrong in your code. 
However, first start with creating a new project. 
In that you can copy parts of your code and then first. Remove that module, it is vintage try OOP programming.
Secondly, use one form, or use dialog (modal) forms (which are shown with showndialog.
There is so much missunderstood by you in your code, that trying to help you would only end that it would even be worse when you start to copy that in your original code.
Here on our website a sample how to do that.
You probably don't need much more code than that.
http://www.vb-tips.com/CommandBuilderDataGridview.ASPX 
Success
Cor