IELTS

you need both. IELTS. is a must to prove your English language test. GRE. if the University asks you have to do prove your engineering aptitude

The International English Language Testing System (IELTS) is a test that measures the language proficiency of people who want to study or work in environments where English is used as a language of communication. An easy-to-use 9-band scale clearly identifies proficiency level, from non-user (band score 1) through to expert (band score 9).

You have to appear for one of ielts or toefl to enter the boundaries of a country. This is mandatory. Gre is college admission in good ranked college. Not mandatory everywhere.

4.5 band is very less and I don't think any country who are accepting this band. You need to work hard and at least try to get 6. After that you can apply for New Zealand

Try taking the foundation programs in English such as ELICOS, ESL etc. They are offered by the universities at the start of the course. Communicate with the universities/colleges for more details and entry into such programs.

Yes, Humber is a good college and very popular even among Indian and international students. Scope after you graduate depends on your own skills and academic grades. The college has good tie ups and provided internships too but email the admission office for such details before applying.
https://international.humber.ca/study-in-canada/apply.html

Hi, international students can work part time while studying but you must look for these part time jobs yourself though the university and international student office will assist you regardless of your IELTS which is mainly used for admissions. After you complete your education you will be provided with career services and internship opportunities , not placement. You must develop your own skills and networks to get a job. Hope it helps.

Hi, you need minimum educational qualifications too to get a job and not only the IELTS score. It is also important for you to know that obtaining work permit for international students is very difficult for international students currently. Please keep checking UK job portals for requirements and other details. Hope it helps.

Yes you can. There are many universities not all can be listed but try Birmingham, Queen, North Hampton and all. Keep in mind that ielts is not the only thing to decide your admission, your academics n extra curricular play a big role

Hi,
Not all universities ask for GRE and work experience, so, you may apply with IELTS band 7 or TOEFL with good percentage (above 75) in Canada.