Try to ensure you are using information that is produced by educational institutions or recognized authorities in the field of study. The URL of the website will give you the first clue, it reveals the type or organization that is responsible for the content:
.ac.uk = Academic institutions in the UK
.com = Commercial sites
.edu = Educational institutions
.gov = Government
.nhs.uk = Health information services in the UK
.org = Non-profit organizations
.mil = Military
.net = Network.
.COM (commercial sites)
-often selling something or designed to entertain.
-does not mean it is unreliable but it MAY not be objective
.ORG (Non-profit Organization)
-often trying to convince or persuade
-should always be cross-checked for bias
.EDU (Educational Institutions)
-Associated with schools, colleges, and universities. Most often their purpose is to inform.
-Be careful of course sites that may be mostly student work instead of expert research
.GOV (US Government or Military)
-generally credible and used to inform
-may change tone and focus depending on the agenda of the currently governing party
-often some of the best sources for statistics and data.
https://libguides.com/evaluating_sources/basics