There are a few steps you need to take:
1) make sure to configure your pricing in the settings -> pricing section of your web panel. You will need a zone that is enabled and a rule.
2) Please also make sure to set a default rule (by clicking the star icon on one of your rules)
3) in settings -> settings under the web form section there is a checkbox to say whether to show an estimate or not. There is also the link to the web booker and a code snippet in that section that can be used to embed it into your web site.