ExamWritePad accommodates all keyboard shortcuts for use in modern foreign language exams.
There are a number of ways to do this and you should try to see what fits you
For example:
AltGr+(letter)
ALT+(numbers on numeric keypad)
If you are not confident doing it this way or cannot get the keys to work, just go to the INSERT tab and click on ACCENT SYMBOLS button to reveal the sidebar, where from there you can select the language of choice.