Heya Lil

24" long (2ft or 61cm)
24" High (2ft or 61cm)
12" wide (1ft or 30.5cm)

That makes it 113.5litre tank or approx 30gal

Coolwater fish
Don't get comet goldfish, the tank would be borderline for 3 fancy ones though.
White cloud minnows in a nice planted tank

Tropical fish ~ heater required
With the height the tank has, 4 Angelfish, 2 bristlenose cats & maybe some nice tetras (not neons, they are small and adult angels will eat them) would look nice, tank planted with Val (will grow tall) and some anubias & java fern on driftwood. Angels prefer soft water (rainwater)

Any of the livebearers, platys, swordtails, mollies, guppies, they make for nice flashy colour, they will breed like rabbits, but they eat their own young, so not many survive to adulthood. These are very hardy type fish.

Some simple easy to care for plants are, Java fern, Anubias, Elodea and Val <---These will survive in low light.
If the tank has some sort of lighting you may be able to get some of the crypts and swords species.

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