You have to qualify exams such as TOEFL , IELTS , GRE. If you want to pursue a course in English language then you will need to have a 6+ score in IELTS and 90+ in TOEFLS. If the university you want to study in needs students to know Germany compulsorily then you have to learn Germany and can have to sit for Germany Proficiency test as well.

I hope my answer helps you. All the very best for your future endeavors!

Hello

For doing masters in mechanical engineering in Germany you have required a bachelor's degree in mechanical engineering and a good gre/gmat score for applying for ms in mechanical engineering in Germany.  Some university and college have their own entrance exam do you have to clear that first to take admission.

But most of the college prefer GRE/gmat score for admission.

Good Luck