Pass Info from Infusionsoft to a third party sign up form

I want to know if there is a possibility to pass info from Infusionsoft and fill in automatically a third party web form?

P.S. I don’t have access to the backend of the web form. It is from an app that we are using to sign up affiliates.

That will depend on a few factors. The first has to do with how information is sent to and received for the webform in question. The elements to populate on the form have names in most cases and those names are used to identify information as it’s sent via the url parameters. If the form does not permit this action, or if the names were not included as part of the elements then it wouldn’t be possible to do that. However, if this is not the case then using an http post form within campaign builder would provide that form population for you.