Rinse the rice under cold water until the water runs clear. In a medium saucepan, combine the rice and water. Bring to a boil over high heat, then reduce heat to low, cover, and simmer for 15 minutes or until the rice is cooked and water is absorbed. Remove from heat and let it sit covered for 5 minutes. Fluff with a fork and set aside to cool.
Heat 1 tablespoon of vegetable oil in a large skillet or wok over medium-high heat. Add the beaten eggs and scramble until just set. Remove eggs from the skillet and set aside.
Add 1 tablespoon of vegetable oil to the skillet. Add the sliced beef and cook for 3-4 minutes until browned and cooked through. Remove beef from the skillet and set aside.
Add the remaining 1 tablespoon of vegetable oil to the skillet. Add the diced chicken and cook for 4-5 minutes until cooked through and lightly browned. Remove chicken from the skillet and set aside with the beef.
In the same skillet, add the chopped onion and minced garlic. Sauté for 2-3 minutes until the onion is translucent and fragrant.
Add the thawed peas and carrots mix to the skillet and cook for 2 minutes, stirring frequently.
Add the cooked rice to the skillet and stir well to combine with the vegetables. Cook for 2-3 minutes, stirring occasionally.
Return the cooked beef, chicken, and scrambled eggs to the skillet. Stir to combine all ingredients evenly.
Add the soy sauce, oyster sauce, sesame oil, ground black pepper, and salt. Stir well to evenly distribute the sauces and seasonings. Cook for an additional 2 minutes, stirring frequently.
Remove from heat and stir in the sliced green onions.
Serve hot.