If you are unsure about what class to take or what materials to access, you should start with the background section of this site. In it, you will find the following:
In the topics section, you will see a guided tour of the three classes, with the choices. I view corporate finance as my bedrock class and valuation and investment philosophies as extensions, but that is just my view. You are welcome to come to your own.
If you need books for these classes, you will find a listing in this section. I use the Applied Corporate Finance book for my corporate finance class, my Investment Valuation book for my valuation class and the investment philosophies book for my investment philosophies class.