Hello dear.. Different College have different dates for admission. You neither mentioned your preference of College nor your preferred place or state so it's quite difficult for me to exactly answer your question. In most of the College/Universities registration starts in the month of March for eg.Jamia Milia Islamia, Christ University, Gautam Buddha University,Banaras Hindu University etc.Here I am suggesting some colleges of Delhi ( as you are from.Delhi) you can apply in following Colleges.

Delhi University- 2ndweek of May (20th May probably) to 1st week of June.

Zakir Hussain College - Delhi- 1st June to  22nd June

Punjab University- 22nd April to 17th May

Daulat RAM College-Delhi- Commencement of online registration starts from May 18/onwards

Hope it helps.

Good Luck