For the second sentence, did you have something like "Most people will probably say it's cold" in mind? It is common to learn that "will" can be translated into Japanese as "でしょう", but this translation is a bit textbook-like and not so common in everyday conversation.

Of course, your sentence is grammatically perfect! But if it were me, I would say it a little more naturally like this: カナダってどんな印象を持っていますか。ほとんどの人は寒いと答えると思います。

私のカナダの印象は「大きくてきれいな自然！」です :)

言語には正解が一つ、と言うことは無くていろんな表現が存在するので、私ヴァージョンの添削をしておきました。

私のカナダの印象は、アメリカと変わらない　ですｗ。文化も英語のアクセントもほとんど同じです。カナダへは2度行き、ミシガンでカナダからのグループの人達と9年ほど一緒に絵付けを学びました。でも、eh?という表現はカナダ独特（ミシガンの人たちも言いますが）ですね。

I didn't point out the strict grammar here because I didn't want to discourage Athlee.

The more "correct" form would be:

カナダにどんな印象を持っていますか。

But in casual, friendly style, カナダってどんな印象を持っていますか is also natural. In spoken Japanese, "〜って" often works like a topic marker ("speaking of ..."), so it doesn't sound strange at all.

That's why I decided not to "fix" it. The original sentence already works well in the friendly style with polite forms Athlee was using.

Athlee-san, feel free to ask if you want strict grammar corrections in the future.

@Una Thank you very much for your valuable comments ! No matter it is the "correct" grammar, or the more natural and casual way of speaking, both are areas for learning for me, both of which are highly appreciated ! カナダは本当に大きくて自然たっぷりですね。

@yumiyumayume コメントありがとうございます！へー、ミシガンの人もehを使いますか？知らなかったです！面白いですね。