Hello Nivas, 

Well to get admission in private colleges through JEE Main scores, you have to attend the respective counselling session of the college. Based on your JEE score, the college will allot a seat to you. Now, if want to get a seat in colleges like NITs,IIITs or GFTIs then you have to attend the JoSAA counselling. Now for that you have to be JEE Main qualified as per your category. The 2019 JEE Main cutoff for GEN-EWS is 78.21 percentile. Since, you have got 80 percentile so you are JEE Main qualified and hence eligible to get a seat. Below I have provided names of some private colleges that accepts JEE Main score - 

• Graphic Era University
• Amity School of Engineering
• Amrita School of Engineering
• Army Institute of Technology
• Chandigarh University
• GITAM University
• ICFAI Foundation for Higher Education
• Institute of Engineering & Management
• Kalinga Institute of Industrial Technology
• Symbiosis Institute of Technology
• Ahmedabad University

You can go through this link and checkout the list of top private colleges in India accepting JEE Main score : https://engineering.careers360.com/colleges/ranking/top-private-engineering-colleges-in-India-accepting-jee-main-score

All the best !!!