Which hook can I use before or after submitting a webform form? I created a webform form with drupal 8.

I would like to populate a database table with information from my form before or after submitting.

I guess there must be a hook like hook_webform_pressave () or hook_webform_insert () but I have not found the solution.

Thank you for your help
Take a look at the answer to Add a custom submission handler to a form. This will tell you how to add a submit handler to a form. You can use the same approach to add a custom submit handler to the webform and then perform the operations you want from the submit handler.