Does using internet service affect my privacy?

Well yes it does affect the privacy but sometimes you can keep it safe by using these method

1. Don't register in unknown websites.
2. Don't register in websites which you don't visit often or don't know what they are offering.
3. Make sure you don't sign up for free newsletters
4. Don't provide your mail id publicly.
5. Also See to it that you always use an different identity [ you can even use a different photo of yours,if required.]

This way your privacy will not be ruined.