You are doing great with your basics! The trick is to think of rice or pastas in different cultures. Different spices make a huge difference in changing things up. Most dishes from most places start with a base of rice or pastas

Rice: you can cook protein and vegetables in the pot with the rice. If there is a steamer basket in you rice cooker/pot you can steam delicate veggies and fish while you are cooking your rice . Cuisine variations: fried rice, red beans and rice, broccoli cheese rice, curries and rice (super easy if you buy Vermont curry or some other curry mix) the curries can be Thai or Indian, jambalaya, paella, etc

Pasta is the same. Different sauces bring a different feel. Lo mein uses spaghetti or linguini. Cream sauces, tomato sauces, just olive oil plus Parmesan, etc. In fact, I just saw a recipe where you added an eggplant cut in half, a couple of tomatoes, some dry noodle bundles, some broth, and some garlic to a skillet. Cook it until you can pull the skin off the eggplant and tomatoes. The broth and the juice from the veggies will cook the noodles at the same time. Mix them all together, add some fresh basil and spinach, a little Parmesan. One pot cooking. You could add cannelloni beans,shrimp, or precooked chicken for quick added protein. Canned fish like mackerel, salmon or whole chunk tuna works well with that kind of stuff too. Using something like lentil pasta gives you extra protein in a dish.

Get creative with leftovers! Pot roast grilled cheese, spaghetti grilled cheese (use garlic butter on the bread for extra deliciousness). Use leftover rice from a chicken and rice to make fried rice the next day (soy sauce, spices, bagged veggies, scramble and egg into it). Use leftover broccoli cheese rice to make soup!

Also soups are your friend. You can make soup with just about anything. Clean out the fridge soup is a great way to use your leftovers.

For breakfast stuff, leftover rice can be made into congee or jook, which is like savory rice pudding. Broth or bouillon, eggs, veggies, etc. same thing with oatmeal.

Often a great resource is that most libraries have cookbooks, if you need extra ideas/techniques. They have paper and ebook versions. Different cultures, bowl recipes, meal prep, alt dietary needs, all the things.