I think the key is to be mentally prepared and have low expectations...
Mostly the idea we have of a place we have never been to is either from the internet, pictures, videos or from people who have been there.... mostly its not completely accurate.. trust your fellow indo-canadians to paint a rosy picture of their lives in canada and blow everything out of proportion...which is usually quite the opposite
Everybody's experience is different, some have it really easy in life... some don't. I know guys who did a 1 year course and got PR.... i also know guys who did a number of courses for 6-7 years but nothing worked out for them. There are a lot of students who have to go back to India because things didnt work out for them. You wouldnt have heard about them because nobody talks about their failures in life but everyone will broadcast their success story to the world. So It all depends on the choices you make, the nature of events when you make those choices and to some point... your luck
You dont have to have relatives etc here but if you do, its a big help.. specially when you leave your cozy home base and the security of your parents, having help here in the beginning goes a long way. Even if its just some advise and guidance. So if you do have distant relatives, reach out to them for help in any way they can.
You can probably make enough through part time work for living expenses but don't count on it because of various reasons:
a. you wont have a work permit for the first 6 months
b. living expenses will vary widely based on the city you live in, type of accomodation, your own lifestyle etc
c. your work schedule will depend on your course schedule
d. availability and the type of work
So its good to think about all these before you decide to come here just for your own piece of mind and your parents too...that does not mean people don't come here without a proper plan. Hundreds of students come to canada with no planning whatso-ever. I've met people who show up without even a place to stay and go straight to a gurdwara or a temple to find shelter. It just boggles my mind that someone can take such a big chance and their parents let them take it. Eventually they figure things out but only after going through a very very difficult time.
As far as thinking about the future goes (like jobs, PR etc), its really hard not to think about it. Specially as an Indian student, we have this fear of future and "what if" instilled in our minds from early age... think about it, you start thinking about what stream you will take in grade 11 right when you are in grade 8 or 9, you start preparing for CET, PMT etc in grade 11, start preparing for Masters while you are in 3'rd year of your bachelors...It's hard not to think about your future but also keeps you sharp and forces you to have a plan...
So i'm sure that older gentleman meant no harm but gave you genuine advise for your own benefit. After all, it is really tough to see someone suffer, specially when you can't do anything to help because of your own limitations. I mean its not too hard for guys if they have to go through a rough patch but i have seen girls coming to canada without knowing anyone, no accomodation etc, no plans of going through the course; all under the mis-conception that once yo get to canada, you are set. Not quite, the real struggle has just begun.
In the end, i won't say don't take a chance because life is all about taking chances, but have a plan A and a plan B. Things do get better but it takes time and hard work.
Good Luck