With this rank, They are very less chances to get a seat through counselling , so I suggest you to get with the private colleges according your preferences. As the admission is based on your rank and general details be sure about the  cut-off marks on the given courses.

You can also get admissions chances  through State level Government & private colleges.

check out link for the colleges: https://engineering.careers360.com/jee-main-college-predictor?utm_source=qna&utm_medium=jee_cp

Hi

I am assuming that you belong to general category

With 42 percentile

• Your  rank will be  around  593340 - 667000 per our rank predictor at

  JEE Main Rank Predictor 2021 - Predict your JEE Main ...

  JEE Main Rank Predictor - Know your expected IIT JEE Main 2021 Rank by ...

On the basis of past year trends,

You can still get cse but in private colleges.

Some of the private   engineering colleges in which you hold a good chance for computer science  are listed below :-

---------)Sister Nivedita University

----------)Modern Institute of Engineering and Technology

----------)Supreme Knowledge Foundation Group of Institutions

And a few more

To have  a personalised and complete list of colleges which you can get on the basis of the category you belong to,  your home state, your gender etc we have jee main college predictor  for which link is provided below

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

To help you  further,

Minimum percentile in jee main 2021 to qualify it to  be eligible for jee advanced 2021 is given below :-

--------) general :-87.8992241 percentile

--------) EWS:- 66.2214845 percentile

--------) OBC-NCL :- 68.0234447 percentile

--------) SC :- 46.8825338 percentile

--------) ST:- 34.6728999 percentile

--------) PH :- 0.0096375 percentile

Thank you