There are multiple sources available over the Internet to learn Potugese and related Historial Perspectives from Colonialism. You may even refer to Wikipedia, which is an excellent source as well as Youtube for in depth study. Apart from this you may refer NCERT Textbooks for Trade, Territory, Advent of Europeans and learn more about Portugese Colonialism in India.

For more information about Portugese do follow the link below

https://www.careers360.com/courses/portuguese-course