Does Appian support multiple versions of same application for different environment(Dev/Test/Production)?

Can you describe what you are trying to achieve? In general each environment is independent, so the design objects on your Production environment won't necessarily match the objects on Develompent. This allows you to do active development without impacting the objects currently in Production.

If the question is whether you can have multiple versions of the same application on the same environment, that is not possible. However, you can create packages to mantain separate repositories where different developers can work independently.

Hi bipindras0001,

as far as I understand you, it is not possible to have Customer "onboarding V1.0", "Customer onboarding V1.2" etc on the same environment
the reason is pretty simple:
an "application" in appian context is nothing else then a kind of logical orchestration of different appian elements. each element has a version by itself. That means if you update an element the logic is "live" and the older one overwritten. But this applies to the specific environment you do changes to.
This means:
there is only one live version of each appian object per environment. so there is no possibility to have different versions of the same application on the same environment. 

example:
you start working on dev environment, all changes you do, are only valid for the DEV environment.
After deploying them to TEST, ther are live on DEV and TEST Environment.
To get the changes on the production environment, you need a "second" deployment to that specific environment.
But in total per environment there is only one valid version of the same application.