katechezprice :
I have just download AV anti virus software. It now tells me I need real time protection which I have to pay for. Is this necessary?
Not likely.
There are a number of free antivirus apps including windows defender.
They protect against known viruses.
For most users, that is adequate.
More sophisticated apps will try to sense new "in the wild" viruses that have not been seen before.
If you are really paranoid, or you frequent sketchy porn sites, then be prepared to pay for a more sophisticated antivirus app.
And.. be prepared to consume added cpu resources in the process.
Regardless of what antivirus app you have, infection is always a possibility.
Prepare yourself for that by implementing some sort of a backup and recovery process.