HeroBook Pro keyboard, symbols issue

Hi!
I just bought a HeroBook Pro, with keyboard as attached pictured.
I chose Portuguese language for the keyboard.
As you can see in the image, some keys have multiple symbols (white, brown, blue). To my surprise, on some keys, white symbols are not available (ex. key located at the left side of backspace key, it includes + and = symbols).
Also, < and > symbols located next to M key, are not available!
Strangely, keyboard does not include Alt Gr key!
Ctrl key seems to have no function!
Is there any key combination that allows direct access to any symbol (white or brown) on any key?
Thanks.
Sérgio