Merging data from different excel sheets into one new sheet

Hi,
I want to merge data from different sheets.
I've come across several problem and i have done some "work" on it, but i'm unable to go further in the resolution of my problem.

Here is the code that i've made and that is working for now

Sub CLEANUP()
For i = 3 To Sheets.Count
    Worksheets(Worksheets(i).Name).Select
    Cleanuptmp = iFindRowDat(Worksheets(Sheets(1).Name).Cells(1, 1).Value, Worksheets(i).Name)
    'Supprime les lignes jusqu'a ce que la premiere lignes soit celle contenant le header du tableau utile
    While Cleanuptmp <> 1
        Cells(Cleanuptmp - 1, 1).EntireRow.Delete
        Cleanuptmp = iFindRowDat(Worksheets(Sheets(1).Name).Cells(1, 1).Value, Worksheets(i).Name)
    Wend
    'Supprime les premieres colonnes si elles sont vident
    While Cells(1, 1).Value = ""
        Cells(1, 1).EntireColumn.Delete
    Wend
    'Supprime la ligne blanche entre le header et les données du tableau
    While Cells(2, 2).Value = ""
    Cells(2, 2).EntireRow.Delete
    Wend
Next i
End Sub

'Trouver la derniere ligne utilisée dans un page
Function LastRow(WorksheetName As String) As Long
        With Worksheets(WorksheetName)
            On Error Resume Next
            LastRow = .Cells.Find("*", .Cells(1), xlFormulas, xlWhole, xlByRows, xlPrevious).Row
            If Err <> 0 Then xlLastRow = 0
            End With
End Function
'Trouver la colonne contenant data, renvoit le numéro de colonne
Function iFindColDatN(Data As String, WorksheetName As String) As Integer
    Worksheets(WorksheetName).Select
    t = 1
    While Cells(1, t) <> Data
        t = t + 1
    Wend
End Function
'Trouver la colonne contenant data, renvoit la lettre de la colonne
Function iFindColDatL(Data As String, WorksheetName As String) As String
        iFindColDatL = ColLet(iFindColDatN(Data, WorksheetName))
End Function
'Converti numéro de colonne en nom de colonne
Function ColLet(ColNum As Integer) As String
        If ColNum > 26 Then
            'Colonne multi lettre
            ColLetr = Chr(Int((ColNum - 1) / 26) + 64) & Chr(((ColNum - 1) Mod 26) + 65)
        Else
            'Colonne mono lettre
            ColLet = Chr(ColNum + 64)
        End If
End Function
'Trouve le numéro de ligne contenant l'information DATA (pour incrémentation et recoupement ultérieur)
Function iFindRowDat(Data As String, WorksheetName As String) As Integer
        Worksheets(WorksheetName).Select
        On Error Resume Next
        iFindRowDat = Cells.Find(Data).Row
        If Err <> 0 Then iFindRowDat = 0
        While 1 <> 0
        
        
        
End Function

I've joined the output that i want, the code that i've mentionned above would be ran from the first page, that will contains some options if needed, and some information regarding the macro usage.

If anyone could help, this would be great.
thx in advance,
Regards,
MrCarembole.