If you haven’t submitted yet your international certification, you can submit it at this page, until the deadline provided. (30th of June 2019, or 31th of July for Spanish certifications).
Otherwise, you can skip this step; this means that your application is completed.
Whit this form it is possible to upload the self-certification in case the student comes from a country where English is an official language.
You can check the final ranking (when available) in the 6th step.