I have created two dashboards having two different datasets but the dimensions and measures are the same. When I select an option in parameter it should load me different dashboard data on the same dashboard sheet.
Yes, it can be done but that better option would be to Union your data itself on the data pane. If still, you want to go ahead with two different data sources, then you can create a calculated field and use parameters in that. Later, you can put both the worksheet in the same container and using the parameter control you can control both the worksheet in the dashboard.