Heyo! I'm also new. I'm curious to see what skins you make!
For your pen problem, try reinstalling your pen drivers. To do so on Windows, you can go to:
Control Panel > Hardware and Sound > Devices and Printers and try to find your pen. Right click it and click Remove Device. Then, try reconnecting it. Windows should reinstall the drivers.
If this doesn't work, try:
Control Panel > Programs > Programs and Features and try looking around for your pen drivers there (sometimes drivers appear there). If not, I'll do some research and let you know.