Encrypt your hard drive: If your computer is stolen, it's easy for anyone who knows what they're doing to get into the computer and your files. Even if you have a Windows password set, that can be easily bypassed. However, encrypting your hard drive(s) makes it impossible for nearly anyone to "hack" your computer. Some newer Windows 10 devices come with Device Encryption enabled. If yours isn't already encrypted and you have a Windows Professional edition, you can utilize the included Bitlocker feature. If you have a Home edition of Windows, you can utilize third-party solutions, such as VeraCrypt (veracrypt.codeplex.com).
Ensure your Wi-Fi is secured: You can have the best antivirus solution, but if your Wi-Fi is open for others to connect (or is easy to hack) then all your computers are vulnerable. You should ensure any Wi-Fi you have is password-protected, which means the connection is also encrypted so others nearby can't capture your online activity from the air waves. There's a few different Wi-Fi security methods and you should use the latest: WPA2. If your Internet service provider installed a wireless router you should also change the default Wi-Fi name and password. Some companies, like Timewarner Cable (now Spectrum) utilize insecure default Wi-Fi names and passwords, making it easy for some people to connect.
Use content filtering if you have children around: The Internet has tons of useful information, while at the same time has tons of worthless information and inappropriate content. Children can even stumble upon this when they aren't looking for it, so it's a big idea to be proactive. Though content filtering can't block all inappropriate content, it can certainly help. I suggest using OpenDNS (www.opendns.com) along with adult supervision.