I'm from India and I want to know if I marry an European girl (Romanian), will I be able to get the nationality and work permit for Spain as she is living in Spain.
Nationality, not immediately. Right to live and work in Spain, yes, unless the authorities determine that you entered into the relationship for the purpose of being able to live and work in Spain.
After living in Spain for some time, you will generally become eligible for naturalization, though there can be additional requirements.
After living in Spain for five years, you will generally acquire a right of permanent residence.