add a webform in a product checkout I would add a webform in the checkout step of a particular product. I need this feature because sometimes the products that i offer needs more information and sometimes the information that i need are different, so the webform that i should show could be change.

I would show the webform during the checkout, i don't want to have a webform that redirect to checkout (commerce webform module i think)
As per my understanding of your question you should follow below steps:


Create a form using Webform and then in Webform >> Advance settings mark that webform as "Available as block".
Now you can see that webform as a block in Blocks page.
In block configuration you can set the option to display that block on specific page.


Let me know when you implement it.