How can one differentiate between opinions and facts? What are some ways to improve this skill?

The difference between a Wikipedia Entry Vs Quora Answer entry perhaps provides a reasonable parallel for the difference between Fact and Opinion.

Ideally fact would not / should not change based on who is answering the question whereas Opinion is what can be widely dependent upon who is answering the question.

If this question is answered by 10 different people .. the answers are likely to be presented very differently (opinion) even when the underlying essence/matter is the same (Fact).

So - by all means study multiple answers to the same question.

some more Google Image search answers curated here! hope this has helped