That's the thing about history, there is no truly unbiased historical source or analysis except for those written by our glorious and brilliant historians, whose objectivity is boundless. What you're encountering is the need for source criticism, which is the cornerstone of any good historical education. Essentially, when you're reading any history - or being taught any history - what you need to do is ask a few very specific questions:

First, who is writing this history? Are they closely related to the event or individual in question? Do they have any obvious biases (e.g. Event X, which devastated my hometown's industrial capability, was a terrible disaster despite the fact that it led to major changes which enriched the rest of the country.)

Second, what are they citing? If their sources are only secondary or tertiary sources, that is an analysis of a record of an historical person or event, or a reaction to an analysis of an historical person or event, are they really talking about history, or are they talking about the analysis of history by other historians? (Hint: They're talking about the analysis.)

Third, why are they writing this? Is it being written to advance a particular broader political goal? For example, are they saying that Socio-Economic System A is inferior to Socio-Economic System B because those who follow A are poorer, but neglect to mention that the ones who follow B have consistently attacked or embargoed or otherwise disrupted the normal operation of those who follow A? This does require you do more reading on the subject, yes, but that's an important part of history - the more you read on the subject, the better you will know it and the better you will know why people say what they're saying.

There are more things to discuss about it, but it's been a very long while since I was in the field, historically speaking, and other users here will be able to elaborate more on how source criticism can help you cut through some of the confusion.