Century Initiative obviously doesn't specify from which countries, it merely mentions skilled immigration as its primary source of growth.
However if you take a step back and wish to argue in good faith, and look at where people did come from when Trudeau decided to open the flood gates 10 years ago, you'll find that India represents roughly 40% of immigrants. I'd say that can be described as "largely", and there is no reason to believe that opening the gates even wider would change those proportions.
And if you argue in good faith, you would admit that that the past is not the future before making that argument. You would admit that Trudeau's policies are not necessarily other people's policies or policy preferences. You also would not in good faith use words like "floodgates" when speaking about human migration.