As Thunderballs said, a Business Plan is the minimum if anyone is to take you serious.
A new business that's abstract and not properly defined would be a more difficult one to sell.
My own preference is for an already established business with owner retiring that you can build on.
Or at least one where if you take over the location of a terminated or pre existing business, you can benefit from the clientele that existed for that business.
It can even be a Franchise too(which I don't often suggest) if it's the right price and conditions.
These require high amounts of initial capital though.
I also like businesses related to your skill set example skilled trade businesses.
Government and Business development assistance may be restricted to certain age groups and to specific types of business so research is very important.
A business you have the utmost confidence and commitment in can still work in Canada's large market.
A business you can start off small and then grow is even better.
Don't be discouraged, but do your due diligence and have a very strong plan.
Not only a business plan, but a fallback plan, don't put all your eggs in one basket plan etc.
If you have a job, hold on to it until the business is established.