1.
The question word "where?"
邊便 = which direction
邊度 = where
邊處 = where(*In old days, no one use it anymore)
2.
我住喺香港。= Correct, same as the following one
我喺香港住。= Correct, same as the preceding one
我住香港。= sounds a bit weird, but we understand what you mean.
3.
日本人好似唔好似中國人? = wrong
日本人似唔似中國人? = Correct, Do Japanese look like chinese?
a. Are both these sentences correct?
b. Are they identical in meaning?
4.
What is the difference in Cantonese between 衣服 and 衫?
衫 = Used in oral, informal
衣服 = Used in writing, formal
5.
I found two words for "work":
工作 (gung1 zok3) = correct
工做 (gung1 zou6) = wrong
6.
What does 得了 mean as a reply to the question 你可唔可以聽日畀封介紹信我?
The correct one should be 得啦(dak1 laa1). It means OK. The nuance sounds like "ok, no problem! don't worry!"