Cook rice noodles according to package instructions, then drain and set aside.
Heat vegetable oil in a large skillet over medium-high heat. Add kielbasa and cook until browned on both sides, about 3-5 minutes. Remove kielbasa and set aside.
In the same skillet, add shrimp and cook until they turn pink, about 2-3 minutes. Remove shrimp and set aside.
Reduce heat to medium, add onion and garlic, and sauté until soft, about 2 minutes.
Add bell pepper and cook for an additional 2 minutes.
Return kielbasa and shrimp to the skillet. Add soy sauce, oyster sauce, chili paste, and sugar. Stir well to combine.
Add cooked noodles to the skillet and toss everything together until the noodles are evenly coated with the sauce.
Serve the noodles topped with a soft-boiled egg, cut in half. Garnish with green onions and sesame seeds.