300K immigrants per year in a country of 40 million? That's 0.7%. Which is also equal to about the death rate in Canada. We're only replacing the people that die with immigrants at that rate of immigration, and with the low birth rate in Canada, that's not huge population growth.
But, yes, we know, you're scared of immigrants. Well, unless you're indigenous, guess what, you are one!! Feel free to hurl some slurs at yourself and maybe punch yourself in the face. A 0.7% immigration rate in Canada is very manageable. It had risen to over 1.0% which was putting a strain on some cities where those people were concentrating, and whoopsie, the government throttled it back.