You didn’t say what you want to do. How successful you are depends on how hard you work, whether you really know your field, how much effort you put in. But, doing this degree will be a great success in and of itself.

There is no guarantee that you will have success. The degree is not a magic bullet which will bring you fame and fortune. Presumably by the time you graduate you will know something, and that will help you be more qualified for a variety of jobs out there. The rest is still up to you.

As for grading at 25, that’s nothing terribly unusual. There are plenty of people out there that started college late, worked their way through school, are returning for their degree, or a slew of other reasons. Graduating at 25 years old is nothing to worry about or to be ashamed of.