For lateral entry, you get direct admission to colleges in the 2nd year of BTech if you have done B.Sc/ Diploma in any relevant subjects(depending on the state and the exam). Most of the state has lateral entry exams which you have to qualify and based on a valid score you can get admission via lateral entry.

Now as you didn't mentioned your state then I can't say which lateral exam you can give.

** In west Bengal, JELET is the exam which is conducted for lateral entry.

I hope this answers helps. All the very best for your future endeavors!