Please if you are asked to forward your cv to an email, is it just the cv you will send or is one supposed to attach a cover letter.please help

Forward CV means send your CV.

You can go a mile more by Attaching a cover letter. I don't think it may cause any harm.

When ever you're asked to forward a CV, always ensure you put a small pitch of yourself as cover note on the body of the mail.
The mail gives an insight of what to expect on the attached document (CV).
Your cover note must be precise and concise.