Take it to Autozone, etc. and have them pull the codes for you. They will usually do it for free or loan you the tool.
You can buy a simple OBDII reader for under $100 anywhere. That will allow you to read codes and reset simple things.
Or you can spend +/-$300 for a Durametric and really tunnel in to Porsche specific issues. You will need a laptop that meets their requirements for it to work. It is a software and cable package.
Diagnostic Tool for Porsche | Durametric
Get the codes and then use the search function to do some background reading and then follow up with questions. Good luck.