Microsoft will be ending support for Windows 7 in January 2020, and that move will leave Windows 7 users with a very important choice to make.
If you have a Windows 7 PC one of the choices you’ll have available to you is to take your chances and keep using Windows 7 even after Microsoft stops releasing critical security updates for it.
I don’t really recommend that due to the reasons stated in the post I linked to above, but if you decide to forge ahead with Windows 7 anyway you can reduce the significant security risk a bit by using a really good antivirus and anti-malware product.
If you’re trusting Microsoft Security Essentials or Windows Defender to keep your PC free of malware, I strongly recommend replacing them with something more effective.