Now that you have the folder (I would have kept it short since these are small screen machines) you can now head to Start, Settings, then the Menus item.
In the "Checked items appear in the Start Menu" you can now show your new folder.
Sorry but I wonder if you are new to Windows Mobile. I don't want you to get frustrated over this old thing. It's not easy to use it natively.
Have you consider installing some shell or skin like SPB Mobile Shell ? I can't tell if you want to forget native and just skin it.
PS. To add shortcuts to your folder, find the app you want and then tap and hold to get the menu, copy then navigate to your folder then click and hold for the menu and Paste Shortcut.