I would like to know when we use "the" for the institutions particularly when it is written in letters or newspapers as title/body.
As far as I understood, you don't put "the" for the title while use "the" for the body in a letter.
For example:
Title: 21st National Assembly or Embassy of the United States in Brazil
Body: The 21st National Assembly has a plenary session..... / The Embassy of the United States expresses its compliments....
Please correct me if I'm wrong.