Quinoa has a unique nutritional profile compared with other grains. However, you can substitute quinoa with other whole grains like brown rice, sorghum, millet, buckwheat, pearl barley, and oats. You can also replace quinoa with legumes such as beans, chickpeas, and lentils. Though they are quite different in taste and texture, the nutritional profile is similar.
I understand that for some people, tofu can be a challenge in the beginning. I really encourage you to give tofu a chance! Different spices can make a huge difference in taste. Moreover, you can find different varieties of tofu, not only neutral ones. Smoked, marinated, or enhanced with different spices, tofu can be a very appealing ingredient in your meal.
If you still feel hesitant about tofu, you can replace it with your favorite beans, chickpeas, or lentils. You can substitute tofu with lean meat cuts, white fish, or seafood too. Just be mindful of consuming proteins from animal and plant sources.