Any help is appreciated and the more detail the better.
Use Application.loadedLevelName to get the name and use a GUIText to display it.
Create a GUIText in the Hierarchy window, then set its properties as follows:
Position: X=1, Y=0, Z=0
Text: none (clear the "Gui Text" original)
Anchor: lower right
Adjust also the Font, Size and Style, then create a script like this and assign it to the GUIText:
guiText.text = Application.loadedLevelName;