We are end users just like you and are all located in different corners of the world. Apple is simply the host of these forums, they do not read or answer any questions. If you buy directly from Apple you CANNOT have the product shipped to a different country that much I know.
To make a purchase, have it sent to your Bangladeshi address and follow the requirements from the on-line store assuming Apple has an online store for Bangladesh. Of course you will need to follow the requirements for sale which may include requesting a student ID or enrollment letter.
If Apple does not sell directly in Bangladesh you can buy from a Bangladeshi reseller and speak to them directly about your student status to see if they can offer a discount. You can search for Bangladesh Apple resellers by simply doing a Google search.
Another option is to have your parents purchase in Dubai and ship the device to you in Bangladesh. They somehow would need to prove student status of course in order to get any student discounts. You will need to research what proof Apple needs in Dubai.
Good luck on your purchase and your studies!