You will find that occasionally there are questions from other units included in the lessons just to keep you on your toes.
It isn't necessary, just spell the word out using roman letters. If you're determined to practice with a Greek keyboard, you'll have to look up instructions specific to the operating system you're using.
Go to settings (apples) general, language, add your preference. Globe symbol on screen keyboard gives you the choice of alphabet you want/nee. Tap to change as needed