Here is a Word document that has all the glyphs (special, alternate characters) in the Samantha font. Once you have Samantha installed on your computer as a font you can open this document in your word processor. Then find a special character you want to use. Then copy is to the clipboard and paste it into your design in Silhouette studio.
If you want to create a similar document listing all the glyphs for a different font, here are the directions on how to do that on a Windows computer: