Why are free apps on my purchased apps? Is that fine?

I don't want to get billed by apps that are free?

Added (1). I have an iphone

Even though they are free you still purchased them from the App Store. So yes that is perfectly normal & no you wouldn't of course be billed for a free app.

The most you'd get is the digital receipt which would show a charge of $0.00.

You won't be charged.

Its perfectly fine don't worry about it and get the best protection by installing Leo Privacy Guard. It will make your device totally secure.