Dear samamoon,
First of all, CONGRATULATIONS.
Please share your timelines or update your profile like mine so that we can make educated guess and assess our cases.
If it is not said anything specific, then I think you are suppose to submit your response to this letter to Singapore Visa Office, not Baridhara, Dhaka. So far I know, our High Commission of Canada does not process Immigration Visas, only correspondences to SGVO.
My suggestion is, you collect all the documents in the list and go to singapore and submit the package (including your passportS) there personally. It will take 3 working days for getting your passport back with the Immigration Visa from there and cost you roughly 50,000 Taka for the tour.
1. Medical Report of full family.
2. Police Certificate (If they asked for new Certificate, March-2011 NOC will not work. PCC used to be valid for 6 Months.)
3. To pay the PR fee : Is it PR fee or Landing Fee. If Landing Fee, make FDD from SCB only.
4. New passport size pictures and
5. Passports.
You can also send Personal Messages if you do not want to disclose your personal credentials with everyone.
Regards,
INDIANAJONES.