If you get a warn from antivirus when visiting a website, exit that website for your safety.
When I suggest and say this “update it regularly” I do it to be safe in cases when update is not accomplished automatically. Although, today most applications and operating systems are automatically updated.
Avoid installing aplications from unknown publishers and do not download them from suspicious sources.
To download an application securely, you need to make sure that you download it from their official site. For example, if you want to install an Adobe app, then you should visit adobe.com. Avoid “free“, “cracked” or “fully activated” from search results.