The answer is no. People usually think that goldfish get lonely and depressed. This is not true. Goldfish are fine on their own! People usually prefer 2 or more
goldfish need to lay eggs. Because if they don't no goldfish would be alive and would not be any more so they would become gone forever.
They prefer one.
Yes, like all pet fish, goldfish need more oxygen than can be provided by just a bowl of water.
No they should not, goldfish like higher vegetable protein levels, where as guppies need more animal protein.Yes.
That you need a new goldfish
Goldfish have scales rather than hair, and as such, they do not shed
They definitely need a air pump, a filter, at least 20 gallons of water for one goldfish, a thermometer, and decorations to improve the goldfish's well-being/mood.
Goldfish need to mature before they can lay eggs and they can get pretty large (6" or more). By the time they are large enough, they have outgrown a fish bowl. So technically, the answer is no. You will need large goldfish in a large tank before you can breed them.
Goldfish cannot live in bowls. Fancy goldfish need at least 20 gallons for the first fish, and 10 gallons minimum for any additional goldfish. This means that for two goldfish, the smallest tank you should have is 30 gallons.
One goldfish requires at minimum a 20 gallon aquarium with a filter, and an air stone would be nice
It all depends on height. If both your goldfish are around the same height they might be playing. But if one of your goldfish is bigger than the other by 2 or more inches (or even by a long shot) the bigger one is bullying the smaller one.