How to add authorization header in POSTMAN environment?

In contemporary releases of Postman, you can just set your auth on the collection (or folder), and have every request inherit it (which I believe new requests do by default).

postman usually remembers your key-value pairs you send in header. So there is no need to add headers each request. Anyway you can configure a "Preset" with your auth token.

Yes, you can do this through Postman by assigning your header as an environment variable, let's say authorization, as follow:

then set you environment variable with its value as follow: