Cheap, small fish: peacock fish, map fish, these two kinds of fish can eat ordinary fish food.
A little cheaper fish: parrot, arhat, lucky, giant salamander parent fish (arhat is very powerful and bites each other), but the fish food is a little expensive. If you give some good fish food, the color will be purer and grow faster. It is best to choose wheat worm feeding.
Expensive big fish: Our family has a silver dragon. I think it's easy to watch my dad raise them. Adjust the temperature, eat one wheat worm a day, eat two or three when you are young, and gradually increase the number when you grow up. Now all my silver dragons can eat loach and shrimp. Jinlong will be more expensive. Don't keep it for beginners, because it's terrible.
I suggest you buy parrots, dolls, parent fish and peacocks together. They all look good. Lucky fish is white, and its scales will glow as they grow bigger. I like it very much.
Personal views are for reference only.