You'll need to call around to see what it will cost you -- Insurance is very personal, so no two people will be quoted the same or even near the same. Choosing something like the CBR300R is a great choice both as a learner's bike and also to keep costs down. The rest will factor in, based on age, postal code, years of experience driving a car, G or learners, any tickets in past 3 years, any accidents in the last 6 years, if you are insuring anything else along with the bike (eg. a car, condo, house, etc).
Assuming you are squeaky clean in terms of past history, driving for a few years, and under 25, any quote under $5000 would likely be reasonable. Know too it should drop dramatically in either year 2 or 3, once they determine you aren't a significant threat to yourself or their bottom line. Also always talk to or email a real living and breathing person...online quote generators are notoriously bad. I can use TD's system to generate a quote for me around $4000-8000, but if i call them, I'll get back a number in the $1200-2000 range. Never understood that one, as it technically can drive business away from them or any company that employs it.
EDIT: Just read your post again and if you are 20 with zero history (as in, you never held any license and literally just got your G1M1), then expect very very high rates for a few years. Right now you are a huge red flag for anyone as you have no history, and while you might be the epitome of a perfect driver...you could also kill yourself in the first kilometre and take out a bunch of pedestrians with you. Only comparison I can give you was a friend who started riding around 18 or 19 with zero history. He bought a CBR125R and I think was paying around $5000-6000/year, at least for first year.
