The spelling "deutsch" is the word German in German. The noun form is Deutsche (German man, plural Deutschen).
The German word for Why is Varrum
The German word for how is wie.
und is and in German
Ich
sind
zu
mien
Wo.
The German word for "book" is "Buch"
At can be translated as an, bei or auf in German.
The German word for mother is Mutter.