1. You will have to watch my free lectures on CAPM because I can’t possibly type them all out here. (Although Beta equity is the beta of equity shares! It is the same thing.)
2. The market value of debt has no direct affect on the company at all. It is the price debt holders are prepared to buy and sell to each other. The company continues to pay interest at the coupon rate on the nominal value, and redeems them at the price stated when it they were first issued, regardless of the market value.
My lectures are a complete free course for F9 and cover everything needed to be able to pass the exam well.