If you intend to come to Portugal for a short-term mobility, you may consider the Erasmus+ Programme.
This Programme includes the European flagship initiative programme, Erasmus, which has been supporting mobility of higher education students for 30 years.
Students (and staff) from the 28 European Union countries, Iceland, Liechtenstein, Norway, Turkey and Macedonia should obtain information on the existing agreements with Portuguese higher education institutions in their higher education.
Through the Erasmus you may benefit from support for mobilities with a duration of 2 to 12 months for studying or internships, in each study cycle and for recent graduates.
Students from other countries may, also, benefit from the International Credit Mobility. Try and obtain information in your higher education institution.
For additional information on these initiatives and other Erasmus+ subprogrammes, you may contact the Portuguese Erasmus+ National Agency for education and training: https://erasmusmais.pt/