I would change your letter like this
"As I am currently learning Japanese in hope of working in Japan after my bachelor's degree in early 2018, I would like to enquire more information about your application requirements.
Though I am not a native English speaker, I do consider myself fluent in English. I have studied in England for a year and passed the CAE level C2. Shortly afterwards, I went to Dutch University to study International Communication for a year, a study program taught entirely in English.
I am also not a English native speaker so this was my own opinion. If someone spot any mistake or misuse of words, please let me know.
Student or Learner