If you want to visit Portugal for work visa , you will need to apply for a work permit visa. Like any other country, Lithuania has a unique set of laws.
If you’re a non-EU citizen hoping to study abroad in Lithuania for more than 90 days, you’ll need to apply for a student visa (Visa D) and a temporary residence permit.
Visa issued for individuals entering Lithuania for the purpose of taking part in business-related activities, the permit is a subcategory of the Schengen C visa.
A Lithuania Visa is mandatory to visit the nation of Lithuania. However, you may not require a Lithuania visa if you hold a Schengen visa.