Hello Samardh,

To be JEE Main qualified , you need to first have cleared the JEE Main cutoff as per your category. Below I have provided 2019 JEE Mains cutoff (percentile) category wise - 

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

Since you have got 81 percentile under GEN-EWS category, so you have qualified JEE Main 2019. Now if you want to get admission in NITs,IIITs or GFTIs then you have to attend the JoSAA counselling to get admission into this institutions. If you don't get a seat through JoSAA, you can apply for CSAB counselling which will start after the end of JoSAA and hence can get seats in NITs,IIITs,SFTIs,GFTIs. And if you want to get admission into colleges where they accept JEE Main marks but doesn't participate in JoSAA then you have to attend the respective counselling of those colleges. 

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

Also, you can visit this link and check the detailed information for CSAB : https://engineering.careers360.com/articles/csab

Good Luck !!!