Kindly visit the website of the Danish Immigration Services and you can also google "Studies in Denmark" and you will be able to find information on which various Danish international colleges offer tuition.
You can apply online for a student visa on the following webpage.
It is the Danish Agency for Recruitment and Integration (SIRI) that takes the final decision on applications for residence permits and not the Embassy. Therefore we cannot tell you when the decision will be made. Once we receive any update from SIRI we will let you know.
The Embassy does not legalize public documents issued in Bangladesh. You are kindly requested to contact the relevant Danish or Finnish authority, which has requested the document.
You need to apply for a student visa for Norway via VFS. You can read more about the procedure, requirements etc. on the following website.