I scored 638.50 marks. Will I receive any mail from the colleges I listed, about selection or rejection of admission request? If yes, when?

Hello Vikrant,
Congratulations for such a good score in MAT. Every year after the declaration of results colleges call candidates for admission. You will also get call from so many colleges which may  have selected or may not have selected.
At this time most of the good colleges have closed their admission process so, they will not call you. They will call you for admission in the next session. If you want to take admission in this session, you have to apply to the colleges you wish to study in according to your score. You might get admission in some good colleges.
I wish you all the best.