Electrical Engineering

Of course, you can do BA after doing diploma in any field.

Masters degree holders earn about INR 671400 more than Bachelors degree holders. The average salary for electrical engineers overall is INR 4766940, and electrical engineering salaries increase widely with just a few years of work experience.

Master's degree holders earn about $10,000 more than Bachelor's degree holders. The average salary for electrical engineers overall is $70,941, and electrical engineering salaries increase dramatically with just a few years of work experience.

There is provision in some banks where you can repay your loan monthly, only after you start working.
You know that you are from a middle class family, so with that mindset you have to stay in Canada. You are mature enough to do a part time job there and meet your expenses and do some savings in spite of asking from you family.
Worry not, you will make a better future there and I personally have never seen anyone being disappointed after landing abroad, especially Canada, so go with firm determination.
About worthiness of EE, just see the job listings on google of Canada, if there are much then good for you else choose something else.

Canada is a great place for engineers and it also provides PR, so don't worry. You will get fruitful result after the successfully completion of MS in electrical engineering.
All the best.

You can go for the following universities according to your GRE profile:
1. California University
2. SDSU
3. University of Illinois
4. Kent University
5. Cleveland University
6. University of Colorado, Denver, etc.

Most of university in Canada is as equal reputed as India's IITs. So, if you are good in academics and don't have financial problem, you must go for Canada. You will have a bright future.
All the best.

Yes, electrical engineering has great prospects in Canadian universities, you can get jobs in renewable sector mainly.