OK, is your brother Canadian and living in Bangladesh with his wife? Or applying under something other than family class? Unfortunately when you apply outland spousal whether or not you are living without your spouse is irrelevant. If he is Canadian and applying spousal and living in Bangladesh he would have to prove he was intending to move back to Canada with her when PR is approved. If it's some other PR application it will be completely different. For you and your wait time it is dependant on the strength of your application, children if any, and very much on the luck of the draw as to which VO yourcar is assigned to as some seem to be considerably faster than others. There is a while Singapore timeline thread btw.
Lots of applicants through Bangladesh and mostly spousal.