hi there,
yes, you can land anywhere you want, but it is highly recommend to have an address in Montreal (or Quebec province) to show your intentions at the POE, since you are under QSW. If you don't have an address here, you might have to answer some questions.
The PR card will be automatically applied for at your landing process, since they ask you for an address. If you don't have an address in Canada, you can apply after, yes, as long as it is in Canada, preferably in Quebec of course.
The PPR letter is something special in a "sentimental" way, but nothing if it comes to the writing/text.
File number, name, and the request. 2 more pages of reading material.
hope it helps