Split multiple lines of richtextbox into word by word into textbox

i tried this:

Private Sub SelectLine(direction As Direction)

Dim lineindex As Integer = currentline + direction
If lineindex < 0 Then
'this is the first line!
Exit Sub
End If

If lineindex > RichTextBox1.Lines.Count - 1 Then
'this is the last line!
Exit Sub
End If

Dim searchedtext = RichTextBox1.Lines(lineindex)
Dim indexofText As Integer = RichTextBox1.Find(searchedtext, RichTextBoxFinds.MatchCase)
RichTextBox1.Select(indexofText, searchedtext.Length)
RichTextBox1.Focus()

End Sub
Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles CheckBox1.CheckedChanged

Dim dataArray() As String = RichTextBox2.Lines(SelectLine).Split(" ")
Dim i As Integer = 1
For Each s As String In dataArray
Dim txt As TextBox = DirectCast(Me.Controls("TextBox" & i), TextBox)
txt.Text = s
i += 1
Next
End Sub


but i am getting below errors:
Error 1:
Severity Code Description Project File Line Suppression State
Error BC30269 'Private Sub SelectLine(direction As Form1.Direction)' has multiple definitions with identical signatures. RichtextBoxLineUpDown C:\Users\OM\Downloads\RichtextBoxLineUpDown\RichtextBoxLineUpDown\RichtextBoxLineUpDown\Form1.vb 18 Active

Error 2:
Severity Code Description Project File Line Suppression State
Error BC30521 Overload resolution failed because no accessible 'SelectLine' is most specific for these arguments:
'Private Sub SelectLine(direction As Form1.Direction)': Not most specific.
'Private Sub SelectLine(direction As Form1.Direction)': Not most specific. RichtextBoxLineUpDown C:\Users\OM\Downloads\RichtextBoxLineUpDown\RichtextBoxLineUpDown\RichtextBoxLineUpDown\Form1.vb 11 Active


Error 3:
Severity Code Description Project File Line Suppression State
Error BC30521 Overload resolution failed because no accessible 'SelectLine' is most specific for these arguments:
'Private Sub SelectLine(direction As Form1.Direction)': Not most specific.
'Private Sub SelectLine(direction As Form1.Direction)': Not most specific. RichtextBoxLineUpDown C:\Users\OM\Downloads\RichtextBoxLineUpDown\RichtextBoxLineUpDown\RichtextBoxLineUpDown\Form1.vb 15 Active


Error 4:
Severity Code Description Project File Line Suppression State
Error BC30516 Overload resolution failed because no accessible 'SelectLine' accepts this number of arguments. RichtextBoxLineUpDown C:\Users\OM\Downloads\RichtextBoxLineUpDown\RichtextBoxLineUpDown\RichtextBoxLineUpDown\Form1.vb 85 Active