Regardless of which OS you are running, there are a number of ways to protect against virus infection whithout using any form of anti virus software.
The obvious one, is not to connect to the internet.
Do not install any program that you are not 100% certain of.
If you do connect to the internet, do not open unsolicited Emails, and never download attachments that you are not 100% certain of, even from people you know.
Use a Firewall. Windows has a Firewall, make sure it is on.
Use an Email account that checks your Emails for virusus.
Keep your OS and software separate from your data, so if you do become infected, you can re-install your OS and software without losing your data.
Do not use Peer to Peer internet sites.
Do not visit dodgey internet sites.
Do not download stuff from internet sites.
These are just basic things that can be done without any special knowledge or training.