Germany

The profile is good. Can you mention your stream in Bachelor degree?

You should first concentrate on your B.Tech, you need to score at least 75% and then you can prepare for IELTS and score 6.5 band. It is a famous and most accepted English Proficiency Exam. You can appear for GRE for boost up your profile, but it is not mandatory.
You can visit www.daad.de, as this websites will help you to give information about various English taught programs, apply for TU9 Universities.
All the best.

Hi
It depends on what specialization you would be looking for and are in sync with your skills and expertise. You may read and research about it a bit more and decide because mechanical is a core branch and can lead to various specialization from automotive, aerospace to photonic.

No, you can easily apply for your Ph.D anywhere in the world, so don't worry.

You are a civil engineer, so you are eligible to apply for both subjects, but for civil engineer transportation is more relevant than geology and in terms of job prospect, both have great prospects. USA and Canada is a better option.

TU9 is bit tough, but Magdeburg, Weimar and also applied science universities like:
1. TH KOLN.
2. HTW – Berlin.
3. JENA.
4. Flensburg and many more.
Your score in GRE and IELTS is quite well.
All the best.

Hello,
Please find the link of top universities: https://www.timeshighereducation.com/world-university-rankings/2016/world-ranking#!/page/0/length/25/country/0/sort_by/rank_label/sort_order/asc

You need to score 75% in Bachelor degree and IELTS: 6 band. You have excellent score, you can try for:
1. TU - Munich,
2. RUHR BOCHUM – Aachen.
3. Other TU9s.

In Germany, there are lots of requirements to get admission in any university. New Zealand is better than Germany. Also Germany is very expensive country. But, you have interested in technologies then German is perfect, because Germany's technologies are one of the best in the world.