Hello,

Depending upon the session in which you're seeking admission, you have to submit your assignments, it's updated at the official website at https://webservices.ignou.ac.in/assignments/bcom.htm, where you also find the last date to submit the documents, generally for July session admission you have to submit assignments till 31st March, and in case of January session it's till 30th September, however extension is offered in both sessions as per previous year trends, but it's better you complete it in due time, the assignments are to be written in your own handwriting,

next you can change your study centre in online mode, for that register at https://ignou.samarth.edu.in/index.php/studentlogin/registration/register, you have to provide your name, programme, and enrollment number, whatever changes you have to make you will find it in the dashboard,

exam are conducted twice a year that is June and December Term End Exam, barring semester wise courses the annual mode happens only once a year, for example if you enrolled in January then you have to appear for December TEE, and if you enrolled in July session you have to appear for June TEE,

IGNOU offers digital version of your study materials which you can check out at http://egyankosh.ac.in/handle/123456789/52465