In Spain they say/En EspaƱa se dice: Soy estudiante. š
The verb Ser is used to talk about: 1. a persons characteristics, eg: Eres amable = You are kind,
2 to talk about somebody's occupation: (Ella) Es mƩdica = She is a doctor; Eres estudiante = You are a student,
3. to tell the time : Son las 10 (diez) menos 7, (siete)
and
...
4. to express the passive voice: Este edificio fue construido en 1798 = This building was built on 1798.
I don't think Spanish-speaking natives would ever use the verb estar in the way you wrote it!
Paul Rothera Spanish advanced student (nivel C1)
I hope this helps you. I š