Dear lamissa,
It's very good hear that you want to study in Bangladesh.I have read your query.I think you can contact with Bangladesh Open University.Thay may be good for you.But I am not sure you are able to attend exam without class.You can visit their website:
Contact addresses of the University :
Main campus
Prof. Dr. Abul Hossain Ahmed Bhuiyan
Registrar (In Charge)
Bangladesh Open University
Board Bazar, Gazipur-1705, Bangladesh
Phone: 88 02 9291112, PABX 88 02 9291101-4/211
Fax: 88 02 9291130, E-mail: shafiqul@bou.edu.bd
City Office
Registrar
Dhaka Regional Resource Centre Building
Government Laboratory School Road, Dhanmondi
Dhaka-1205, Bangladesh, Phone: 88 02 9673669
Fax: 88 02 9291130, E-mail: shafiqul@bou.edu.bd