Kiery1105,
Never get just one goose. They really need the interaction with their own kind. If you already have some, that might be okay, but you may have to separate them at some point, even with two.
You've got a better shot at integrating them if you don't raise them wth the ducks. They'll imprint on the ducks, and that might be great when they're small, but they'll think of themselves as ducks, not geese. They need to learn how to be geese before they learn to get along with ducks. Once they grow larger than the ducks, you could have a real problem with the geese bullying the ducks. Same goes for chickens and other small birds.
They are far more likely to get along if they're raised in sight of each other, but not in the same flock. They can be the same sex, but you really need 2 minimum. Mine seem to be most comfortable in a minimum group of three. I've also raised guineas with goslings and chicks with goslings. It was fine for the sibling geese, but both the guineas and chickens grew up thinking they were geese. We finally had to dispatch both the Guinea Mafia and the Roosters. The guineas ran the younger geese so badly (one month younger) that they nearly killed one young goose and permanently crippled my biggest gander in that group. They were my original Buff geese. The young roosters hit puberty and actually killed 1 gosling the was 2 months old. We thought it was a racoon, but on broad daylight in the afternoon? I caught them in the act with their second victim. I really wouldn't recommend it. They're not like kittens or puppies. They imprint and it sticks for life. We don't always think through all the ramifications of future behavioral problems when we put them together. Better safe than. Oh, sold geese to someone who abandoned them to her chickens. They had serious problems. Ruined those geese permanently and lost several chickens in the process.