For 2 what do you say if there is some kind of exit contract like NDA.
If you’re going somewhere that isn’t NDA heavy, you can speak in general terms without violating the letter of your NDA and it’ll be fine.
If you’re going somewhere that is NDA heavy and has a culture of corporate secrecy, demonstrating that you will not pierce the veil of your NDA of your previous employer at all, neither in letter nor in spirit, will actually help your prospects.
For example, if the company was doing something you felt was evil That you can't specifically mention, then just say That you disagreed with an important strategic decision. Explain what you did to handle it in generic terms, such as talking with your manager, writing up a memo, quitting the company, etc