Pubmed.gov - US National Library of Medicine - research publications. Used by medical professionals.
https://consensus.app - ask anything health related. This site will find more relevant content than Google. It’s like Pubmed.gov, but more casual, minimal and simpler UI. The design is very user-friendly for everyday folks searching the internet. However, it still shows content from medical publications, so it is filled with big fancy words just like the results in more serious repositories.
There are also
Crossref.org - but that has very few articles. Not even worth visiting.
Webmd.com - Bad search. Not reputable for research or serious conditions. Not recommended to answer a specific question. Just Google it instead to get better results. However, it’s a great site to browse and read about random topics, or sign up for their mailing list. It does have a lot of good basic advice for general health, and some good articles based on current events.