Hii

Yes CLAT 2019 will be offline this year i.e pen paper based. This is the entrance test for Law courses. 
To score good and get into NLUs you will require the correct information and help. SO here is a link which you can use to know the syllabus, preparation tips and best books.
If you go on studying smartly you will surely score high and get a good college
https://law.careers360.com/articles/clat-2019

I would suggest you to start studies now only and do not wait for boards to get over. Start by devoting atleast 1 hour a day to your CLAT preparations and after your boards increase the time of study. 
Choose the correct study material and be honest and dedicated to your study.
For more help refer to following link

https://law.careers360.com/articles/how-prepare-for-clat-2019-without-coaching

Thanks!