Well, I want to send an e-mail when the web form is submitted, and when it is edited, so how can I do this? The employee fills a form, and submit it, an email have to be sent to the boss, then, the boss approved or denied the form, and e mail is sent to the employee.
If you look here : http://drupalcontrib.org/api/drupal/contributions!webform!webform.api.php/group/webform_hooks/7 , you'll see that Webform provides some hooks on which you can act.
There's a hook called 'hook_webform_submission_update', which triggers on the update of a submission. Using that one, you can check if the boss approved/denied it, and send out an email.
The plain 'send email on submission' can be configured through Webform itself, so you won't need to use a Webform hook for that. Although you could if you want to.
There is "Webform Rules" which does exactly what you are looking for (Rules integration on Webforms). Here is a quote about it (from the module's project page):
... adds rules integration on webforms.
Did you ever want to react on webform submission using rules but couldn't find the proper event? Webform Rules makes it possible to catch webform submissions by rules and do whatever you'd like to do with it (meaning: do whatever rules let you do with it).
While it is possible to edit webform submissions, it doesn't seem convenient and I'm not sure if it can trigger actions such as sending email.
Another way would be creating a new content type for your questions, allow users to create new content of that type, and define some rules (with Rules module) for sending email.