Questions regarding to University of Toronto Application

Five different IGCSE/GCSE/Ordinary Level academic subjects AND three different A Level/International A Level academic subjects. Prospective students presenting four AS subjects in lieu of three A Levels will also be considered for most programs.

The above is the line from their website. Does this mean if I have 4 A levels I don't need to take 5 IGCSEs?
I'm not from the UK nor from Canada which is why 5 IGCSE is not a must, but I did take a levels

also in their website they states that for computer science they need an english in IGCSE or A level, but then when I search their english language requirement, they also stated that I can use IELTs. So can I just do IELTs without IGCSE english?