composing mail in german

WELL, this didn't help very much ... I am certain there is a setting somewhere within MacMail, it must have something to do with the spellcheck for preferred languages. Unfortunately, I'm very old, and also new to this "game" - I've wasted hours trying to find it. Thought this was a way to get some expert advice....

Checked Google Translate. That didn't help at all - I don't need help with translating, it's the written word - i.e. the different characters used for some letters - that I'm trying to find. It's very awkward and unprofessional having to use "ue" or "ae" instead of the required "Umlaut", the two little dots on top of the u or a .... I'll keep searching.....

Works like a charm, thank you so much!!!