One thing that I think all Oxford students can agree on is that eating in hall can get boring sometimes. However, luckily there are some great food options outside of colleges.
On the cheaper end of the food options there are the well-known 50% of food at Wasabi after 7:30pm and Itsu after 8pm. However, if you don't want sushi, there are other options. Other than their ice cream, G&D's also do good bagels for around £5-7. Additionally, both Italiamo (£3.50-£5) and Café Crème (similar prices to Italiamo) on Broad Street are good for a quick lunch.
Around the middle of the food option spectrum (usually £8-£11) there are some more good options such as the Chinese restaurant Tse Noodle on Ship Street (they only accept cash) which is a nice and cosy restaurant though it can get very busy on the weekends. Both the Covered Market (some places here like Brother's Café will do student discount) and Gloucester Green food market (Wed-Sat) are good options for food and there are many different cuisines to choose from, great if you are going as a large group so people can have a large range of choice. If you live up in Jericho, a good option is Jericho Café which can also double as a good place to study.
If there is a special occasion or it’s someone's birthday, there are also some very nice restaurants to choose from (around £15-£25). Back in Jericho there is Turf Tavern which is a nice pub to go to. Also, Mamma Mia Pizzeria has delicious Italian food, there's also some nice tapas food at Al-Andalus. Adding onto the international theme, Pierre Victoire is good for French cuisine. Further up in Park Town, there is Gees Restaurant and Bar which comes with good recommendations. Around the centre, Quod makes a very nice birthday dinner (especially in winter when they have lights up). Bangkok House and Chiang Mai Kitchen both serve great Thai cuisine. If you are out in Cowley, there are also some nice restaurants such as Chinese restaurant Zhangji.
Hopefully, this provides some food inspiration and enjoy eating!