I think most of us would be discouraged if we had to face [new] challenges, especially me, as I want to study and live in a completely foreign environment in Canada. 1. "challenges and difficulties": English has a strong preference against redundancy (=excess words that have the same or similar meanings), much more than Chinese. 2. "me who": avoid using relative clauses after pronouns 3. "strange environment": this is not wrong at all, "strange" can indeed mean "new, foreign". However, "strange" more commonly means "weird", so it could lead to misunderstanding. It's better to use a less ambiguous word. The only real "mistake" was 2. 1. and 3. are just suggestions to improve the style.

I woiuldIf we had to face challenges and difficulties, I think most of us would be discouraged especially for someone like me who wants to study and live in a completely different environment in Canada.