1. Cook the lo mein noodles according to package instructions. Drain and set aside.
2. Heat the vegetable oil in a wok over medium-high heat. Add the garlic and stir-fry for 30 seconds.
3. Add the bell peppers, carrots, and broccoli. Stir-fry for 3-4 minutes until vegetables are tender-crisp.
4. Add the cooked noodles to the wok. Pour in the soy sauce, oyster sauce, and sesame oil. Toss everything together until well combined and heated through.