Is it necessary to complete one or two courses before going to Germany for studies for a Master's/Bachelor's?

No, you do not need to complete extra courses before applying to study in Germany. With your Bachelor's in Electronics and Communication Engineering, you can apply directly for a Master's program.

Make sure you meet each university’s specific admission requirements, which may include a language test like IELTS or TOEFL. As an Indian student, you will also need an APS certificate from the German Embassy in New Delhi. Processing for APS typically takes 3 - 4 weeks and is subject to change.