The course Full Stack Web Development is offered by the University of Helsinki (see https://fullstackopen.com/). It is offered fully online. To complete the course and include it into your studies at Aalto, attend the course as follows.
Complete the course following the guidelines at https://fullstackopen.com/, also taking the exam at the University of Helsinki. Contrary to the guidelines on the site, take the course with at least 5 ECTS (i.e. the 3 ECTS version is not accepted).
Once you have completed the course, submit the course certificate and the transcript ("opintosuoritusote" in Finnish) -- which you can request after completing the course and the exam -- to MyCourses using the assignment activity below. A link to "opintopolku" that shows your course completion also suffices.