How can someone from Canada get a Japanese Passport?
If you are not of Japanese heritage, you would need to live in Japan and naturalize as a citizen. Today many are doing just that. Hidesato Sakakibara's answer to How can a foreigner become a Japanese citizen? The process is very straightforward, and the level of Japanese language required is that of about a third grader. Note that Permanent Residency is NOT a prequisite for Japanese nationality. You also do not have to renounce your other nationality. You must make a declaration to the Japanese government that you choose Japanese nationality but that is an internal Japanese government procedure that does not involve your original government. Please see my link above for more details.