They have food from various cultures but I dont stray too far from what I know. You can get plain rice,chicken fried rice,vegetables (though notably doused in butter),beef meals,chicken meals,and fish meals.
Just to give you an idea of what you could get and the prices. I got a whole chicken (lemon herb) today for 12.99 dirham (3.50 US) . They also have 3 or 4 other types of seasoned chicken
If youre not into meat, you can get potato salad, hummus, cold slaw,or arabic salad for around 5 dirham for 1 serving which is less than 2 dollars.
The deli has pretty good options if you are close to a supermarket. Although I LOVE shwarma, I wouldnt recommend trying to live on it for any extended amount of time though you HAVE to try it when you get here.