show sheets into userform...

[RobDog888]

Then you can load your userform with this code behind it. The UF contains a combobox control which is probably best to use in this situation.

Private Sub UserForm_Initialize()
    Dim ar() As String
    Dim i As Integer
    
    ar = Split(ThisWorkbook.ListSheets, ";")
    For i = 0 To UBound(ar)
        ComboBox1.AddItem ar(i)
    Next
    Erase ar
End Sub