In Microsoft Word
To add an accent: Hold CTRL and the ‘ keys down at the same time. Release the keys and hit the vowel button. You should have an accented vowel.
To add an ñ: Hold CTRL, SHIFT and the ~ keys down at the same time. Release the keys and type your n. You should have an ñ.
To add ¿: Hold CTRL, SHIFT, ALT and ? keys down at the same time. You should have an upside down question mark.
To add ¡: Hold CTRL, SHIFT, ALT and 1 keys down at the same time. You should have an upside down exclamation point.
You can always use the INSERT and then SYMBOL commands and insert each vowel individually.