Work space and numration area relation

Do I need to create a new work space for every numration area or in the same work space ? We are Trying to fetch data from survey solution for data manipulation and reporting

It’s unclear what you want to achieve.
The idea of workspaces is the way to create separated areas of data collection in Survey Solutions.
It could be one organization that has several departments and doing different surveys, or different teams in one department, collecting data for different projects but using the same scope of enumerators. You may also have just one workspace and organize your work inside it.
If you are using API to fetch data you should specify workspace you are working with.