Private counter As Integer

Private Sub UserForm_Initialize()
    counter = 1
End Sub

Private Sub btn_AddDualControl_Click()
    ' Increment counter for new textbox naming
    counter = counter + 1

    ' Get reference to last textboxes for positioning
    Dim lastControlBox As MSForms.TextBox
    Dim lastTCBox As MSForms.TextBox
    Set lastControlBox = Me.Controls("txt_DualControl" & (counter - 1))
    Set lastTCBox = Me.Controls("txt_DualTC" & (counter - 1))

    ' Create new textboxes
    Dim newControlBox As MSForms.TextBox
    Dim newTCBox As MSForms.TextBox

    ' Create and set properties for Control description textbox
    Set newControlBox = Me.Controls.Add("Forms.TextBox.1", "txt_DualControl" & counter)
    With newControlBox
        .Left = lastControlBox.Left
        .Top = lastControlBox.Top + lastControlBox.Height + 5
        .Width = lastControlBox.Width
        .Height = lastControlBox.Height
    End With

    ' Create and set properties for Task Card textbox
    Set newTCBox = Me.Controls.Add("Forms.TextBox.1", "txt_DualTC" & counter)
    With newTCBox
        .Left = lastTCBox.Left
        .Top = lastTCBox.Top + lastTCBox.Height + 5
        .Width = lastTCBox.Width
        .Height = lastTCBox.Height
    End With

    ' Add new row to the table in the document
    Dim cc As ContentControl
    Dim tbl As Table

    ' Find the content control by its tag
    For Each cc In ActiveDocument.ContentControls
        If cc.Tag = "box_DualTCs" Then
            Set tbl = cc.Range.Tables(1)
            ' Add new row to the table
            tbl.Rows.Add
            Exit For
        End If
    Next cc
End Sub

Public Sub TransferDataToTable()
    Dim cc As ContentControl
    Dim tbl As Table
    Dim i As Integer

    ' Find the content control and its table
    For Each cc In ActiveDocument.ContentControls
        If cc.Tag = "box_DualTCs" Then
            Set tbl = cc.Range.Tables(1)

            ' Loop through all textbox pairs and add their data to the table
            For i = 1 To counter
                Dim controlBox As MSForms.TextBox
                Dim tcBox As MSForms.TextBox

                Set controlBox = Me.Controls("txt_DualControl" & i)
                Set tcBox = Me.Controls("txt_DualTC" & i)

                ' Add data to table
                tbl.Rows(i).Cells(1).Range.Text = controlBox.Text
                tbl.Rows(i).Cells(2).Range.Text = tcBox.Text
            Next i

            Exit For
        End If
    Next cc
End Sub