Knowing if a site is legit in order to keep your computer secure is a task that you need to be proactive with, regardless of whether you have anti-malware software installed. Most malware software is only good after the first few people have gotten infected and reports it. Don’t let that be you.
Ensure that you are spelling the website correctly; going to http://www.gogle.com could send you somewhere else when you’re looking for http://www.google.com, (Google owns gogle.com for those who do make this mistake.) When viewing websites from an email, it is best to go to their web page and find the link from there. This is time consuming, but when you are unsure about the email it is safer. Most spam that carry malware will send you an email that looks like it’s from a trusted site or have a name that is close to the site you seek.