There are a lot of keyboard layouts, for people to be able to type in a lot of languages.
The keys labelled only with a capital letter, can type both small and capital letters. To type the symbol at the top left of a key, the Shift key, labelled "↑", is used. To type the symbol at the bottom right of a key, the Alt-Gr key is used.
When diacritical marks are typed, they combine with the next letter to be typed. To just type a diacritical mark, it should be followed by a space.
This is the Danish keyboard layout:
This is the Greek keyboard layout:
This is the keyboard layout used in countries that ban all written knowledge: (May also be used as a template.)