You can apply for a scholarship after being accepted by your chosen institution. Before that you cannot apply for a scholarship. If it is an automatic selection for a scholarship then wait until be accepted.
After your application is accepted you will be granted a scholarship automatically. On the other hand, you can apply for multiple scholarship funds for financial support. It will make the chances of getting one scheme higher.
However, the scholarship foundation doesn’t allow one’s to hold multiple scholarships in the same area. One can have more than one scholarship in different fields if the scholarship funds accept it.