Websites can be a useful source of information, but before using the information consider if they are fit for purpose. Look carefully at who has produced them, are they reputable, reliable, up-to-date? Most will not be academic but the content may still be relevant.
If you would like to suggest a website to include here - email me
Healthtalk.org - information about health issues, by sharing people's real-life experiences. You can watch people sharing their stories about cancer, autism, motor-neurone disease, pregnancy, drugs, depression and much more.
National Institute for Health and Care Excellence - evidence-based guidance.