If you wish to visit Portugal for a short period of time, you must obtain a visa prior to entry if you come from a *country with a visa requirement for entering Portugal.
A visa is only intended to allow a foreign national to visit Portugal and/or the other Schengen countries** for a limited period of time (90 days). If you wish to reside in Portugal for an extended period of time (more than three months), you need to apply for a long term visa (Residence and Work Permit).
The possession of a visa does not confer an automatic right of entry to a Schengen country. The visa holder is requested to present proof that they fulfill the entry conditions at the border (valid travel document, valid visa, and valid purpose of travel with adequate means of travel).
** Schengen countries: Austria, Belgium, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, and Switzerland.Next