Absolutely! I use this with my clients and in the communities I build. I gave it to my college-age daughter, and she found it amazingly helpful. I have applied these profound principles and concepts to my life, and they have saved me so much heartache and distraction and drama that is unnecessary and draining. This is definitely wisdom for everyday life.
Yes. For example the second agreement, "Dont take anything personal", examines how there is no need to be acccepted by others, nothing others appear to think about you is really about you is really about them.