http://ssd.iykpqm7jiradoeezzkhj7c4b33g4hbgfwelht2evxxeicbpjy44c7ead.onion/ps/module/how-avoid-phishing-attacks
This isn't foolproof—antivirus often fails to detect new malware or targeted attacks—but it is better than nothing. However, note that any file or link that you upload to a public website, such as VirusTotal or Google Drive, can be viewed by anyone working for that company, or possibly anyone with access to that website, such as in the case of VirusTotal.