Hello Prasoon,

Well to get admission into colleges one has to attend the counselling session of that college. Now if you want to join colleges like NITs,IIITs or GFTIs for them you have to go through JoSAA counselling. For colleges other than NITs,IIITs,GFTIs i.e. for colleges those who accept JEE Main score , you have to attedend the respective counselling process for that college. Now for admission through JoSAA , you need to first be JEE Main qualified as per your category. Below I have provided 2019 JEE Main cutoff (perecentile) category wise : 

• CRL : 89.75
• GEN-EWS : 78.21
• OBC-NCL : 74.31
• SC : 54.01
• ST : 44.33
• PwD : 0.11

If you have cleared the cutoff as per your category then you can get a seat through JoSAA counselling. For other colleges that don't participate in JoSAA make sure to attend that colleges counselling session.

You can go through this link and checkout the details about JoSAA counselling : https://engineering.careers360.com/articles/josaa-counselling

If you are JEE Main qualified, but didn't get a seat through JoSAA, then you can apply for CSAB counselling to get a seat in NITs,IIITs,GFTIs,SFTIs. CSAB counselling will begin after the JoSAA counsellings ends. You can visit this link amd check the details regarding CSAB counselling : https://engineering.careers360.com/articles/csab

Hope that you get a good college. Good Luck !!!!