Please how do I have e-mail feature to my website

Please clarify your question.

If I read your question correctly, you have a website that is hosted by some hosting service which is also providing you with e-mail hosting.

Do you just want to access that e-mail account? (Then typically you just need to configure an email client to point to it -- most email clients will walk you throug it.)

Or do you want to add something to your website that permits customers to send you email?

The simplest way to do that is to add a link using the mailto:
scheme -- which works in most siturations as long as the user has an email client configured. There are more sophisticated ways to do it, but if you just provide the mailto: with your email address in a readable format, the user can contact you one way or the other. The downside of that is that webcrawlers could harvest that email and spam it, so you'll want a good spam filter on that email address, otherwise you'll want to go with a more sophisticated system with captcha's etc...