Canada

You will need following things:
1) Your high school transcript
2) Teacher's recommendation
3) Counselor recommendation
4) Extra-curricular activities
5) Standardized tests scores like SAT, TOEFL, IELTS and SAT subject test

Hi,
Write to the universities, as a prospective Ph.D applicant. You must start networking. Check which universities currently offer research studies in your area. Email them, share your research thoughts and questions. They must show interest in you too. You will need some good recommendations too. Take your IELTS. The formal application process should start once you are accepted by research head.

It would be better if you go for MS in Canada rather than PGD.

If you want to go to Canada then you have to increase your IELTS from your current score to 7 overall. It is the same for other countries also.
If you want to go for work then you are required to score 6.5 overall.

Canada is best for civil engineering as construction work goes on in Canada, so in terms of job prospects also it is beneficial.

What is the certificate Masters programme? If you are asking about Master's degree, Canadian universities have one of the best and very competitive. They also do not accept 3 year Bachelor's degree from India typically.