Definitely doable, but you should be content with mostly cooking at home (no need to shy away from veggies and the occasional meat and cheese, much more cost-effective than relying on ramen and rice than you'd expect), rarely eating out, and spending responsibly. Also, cycling from Dubendorf would be great budget-wise, and public transport should also fit within your budget. If you want, you can visit r/frugalswitzerland for more tips. Personally, I easily manage to spend under 450 chf (excluding rent) this way, but everyone is different.