My story is going to have 4 main characters. Can these 4 characters have the same ambition but different goals or should they all be different?
They can all have the same ambition, but I think you'd need to ensure their ways of pursuing it were quite different to each others.
I thought so just wasnt sure. My distinction is ambition is what does the character want abstractly and their goal is what they want concretely.
Interesting. In that case, my ensemble-protagonists are generally working together on the same goal, but with different ambitions for what the shared goal means for each of them. The protagonists of my Urban Fantasy WIP are a crew of drug dealers turned bank robbers whose goal is to make a living: Alec's ambition is for him and his friends Amy and Charlie to become big enough players in the criminal underworld that Charlie can force their rivals to do whatever she wants them to do Charlie's ambition is to find an equilibrium level where she and her friends Alec and Amy can live comfortably without being threatened Amy's ambition is for her friends Alec, Charlie, and her brother Jason to become big enough in the criminal underworld that nobody else can tell them what to do Jason's ambition is for him and his sister Amy to make enough of a nest egg that they can get out of a life of crime
The difference in ambition is a great way to stir up drama, just like differing beliefs. Odds are the conflict as a result will contribute to the plot.
It sounds like you have a pretty good start for an ensemble drama. You might need to flesh out more completely what you're thinking, but there's no problem with doing something like what you're thinking, and depending on your setting that's what makes some ensembles great. I mean, look at any medical drama on TV - they all want to succeed as doctors, but they're different people with different reasons and different motivations. I'm writing a cable news ensemble drama - almost everyone's goal is to be a successful TV reporter, but they all have vastly different reasons why that's important - the villain wants it because she's an ideologue who wants the power to shape how people think, the protagonist wants it because she really cares about the truth and because she needs to feel like her life has meaning, the fashion reporter is trying to show her doctors-and-lawyers family that she isn't a screw-up and has a "real job", the morally gray character is doing it because she wants success and adulation but doesn't actually care about the news, the morning show girl is doing it because she's scared to death that she'll end up back in her dead-end hometown in yet another abusive relationship, and the alcoholic self-proclaimed "news babe" is doing it because she's needs fame to compensate for the guilt she feels for giving up on her idealistic dreams. So, yeah, of course your team can all want the same thing - but if they're all doing the same things for different reasons, they get ver different results and react differently to similar inputs.