Many people keep goldfish at home. But the goldfish they keep often die within a few days. In fact goldfish can live for a long time if you keep them in a right way.
First, you shouldn't keep goldfish in a bowl. Goldfish cannot swim freely in bowls. You'd better put them into a big fish tank.
Goldfish look great but they make lot of rubbish every day. They eat a lot. That is why you need to change their water frequently.
Some goldfish are very smart. When people go to feed them, they will come to the top of the water. But it is not good to feed them too much. Goldfish will keep eating if you feed them. So you'd better feed them at a regular time.
Goldfish and tropical fish come from different environments. Tropical fish like warm water. So you'd better not put tropical fish into a goldfish tank.