332041 Phonetic Alphabet Converter C#

I want this to be done using C#. It should be a WPF application. The function of this application is that it converts the content in the input-box to NATO's Phonetic alphabet. I've attached a picture of how I want it to convert the input. When you hit enter in the input, it should add a coloured [ENTER] in the linebreak of the output. When you have a single space in the input, it should add a coloured [SPACE] in the output. Whenever you add a letter that doesn't excist in the dictionary, it should just output it without converting it. Like the question mark in my example picture. That's it. I'd appreciate clean code.