Olive et Gourmando in Old Montreal isn’t too far away, for takeout baked goods, salads, light lunches. Might be considered pricey by some grad students, but cheaper than a fancy meal.
Chinatown is close, too.
Lots of good cheap eats on the Plateau, which isn’t far by taxi, subway or a walk. Quite a few Portuguese chicken places that are affordable.
The food in Montreal offers a lot of bang for the buck, relative to Toronto and big American cities.
There are lots of parks in Montreal, if you choose to get takeout , and eat in a park, rather than a patio.
I haven’t been to Montreal since Nov 2019 due to Covid, so I’m not sure which places have patios, apart from places I’ve visited in the past .
Might also consider visiting Jean Talon Market and getting food to go.
There is a Mexican restaurant with a patio near the market https://leroidutaco.com/
St Viateur and Fairmont Bagels are affordable. They sell cream cheese at the bagel bakeries. No seating and no patios.
Shawarma and falafel, and other Middle Eastern food, is very good in Montreal. Some is very affordable.
Here’s a thread on Le Petit Alep report (Montreal, long) which is midrange
