Question

what is the fundamental attribution error and the self-serving bias/actor-observer bias and some suggestions as to how to avoid those errors.

Answer 1

(Look them up yourself.) Avoid them by accepting credit--bad or good--for your actions. Don't make excuses for yourself, "I failed the course because I had a hard professor." Similarly, don't judge people solely on their ability or intellect, "Steve probably flunked out because he can't handle work involving too much thinking."

That was mostly FA error. The rest you should read about--and form your own scenarios/ see how you and others falter in your own life (rather then me telling you them straight out).

Additionally, many things are due to chance (luck) rather than what you want to believe to be the cause.