I wrote many a game (nothing released, just fun stuff for me) on my MacBook Air 12-ish years ago. A small group isn't going to be making some giant triple A title with bleeding edge graphics. Small screens can be an issue sometimes (I wrote a few C++ and OpenGL apps on an original eeePC while traveling so I understand) but if you use the windowing features (Stage Manager in the next version of macOS, Mission Control in the current version) things are easier.
Personally for school I think the Air is a perfect machine because it's small/light enough to lug around to class, relatively affordable compared to other Macs, and way more powerful than people realize. I used to run Unity, Maya, ZBrush, Xcode, Modo, Houdini, and many others I'm probably forgetting on mine.
And as another poster mentioned...Java? Uh... Personally I would pick an engine (Unity, Godot, etc) and focus on the language of that engine because the engine will build to multiple platforms.
That being said, it sounds like you guys are brand new to game development so let me offer some advice in that regard:
-DO NOT I REPEAT DO NOT get caught up in tech arguments (x language is better than y, x engine is better than y). You can argue all day but if you're not releasing a game the argument is doing you no good. Lots of beginners (not saying you just in general) will be like "I need to use Unreal but instead of Blue Prints I'm going to roll my own solution in C++" ... yet these people can't make Tetris or Pong. If you don't know the fundamentals/basics no engine is going to make your game better. Make games, not arguments.
And on the topic of engines: For engines, I used to love Unity but have switched to Godot recently, I just like it way better. Your milage may vary. The engine really isn't important unless you're a AAA studio, finishing the game is.
-Don't expect school to teach you and don't wait to learn. I learned how to make games in high school with a book on game development in C. My school had no computer classes I just learned on my own (this was the mid-90s). If you wait for the school to teach you what you need to know you'll be failing to get a job by the time you leave because your peers dove in in their spare time and made stuff rather than wait.
-Start small. I can't stress the importance of this. A small, polished game will teach you infinitely more than a large unfinished project. And by small I mean MICRO. Your first game should be something moving a dot on the screen to a goal. Too many people follow guides/tutorials and then end up lost when it comes to making their own projects because they were busy following a recipe instead of learning to cook.
-With programming: You will get stuck, you will think you're terrible at it, you'll want to give up. This is literally part of programming and doesn't really go away, you just get better at dealing with it. Many times things will click when you skip over them and learn a different concept. It takes time and practice and writing code is a skill so you have to do it to get good at it.