hi,

see if you are planning to study in foreign university it would be best to go for advance level english. however level is also defined diferenly in english course provider institution. for cambridge english proficiency scale,

C2 Proficiency scale indicates  that you have mastered English to an exceptional level.   C2 is equivalent to reaching native-like fluency in language makes the speaker to express him/herself spontaneously, very fluently and precisely,

Band scores of 8.5 and higher are recognised as C2 in ielts level.