how can i know my result if I do not know security pin
Jahnavi, to get your JEE Mains results, you need to visit their official website link: http://ntaresults.nic.in/resultservices/JEEMain-January-2020-auth and enter your application number, date of birth and security pin.
Now just below the textfield where you are supposed to enter the security pin, you can find a rectangular box with 6 alphanumeric characters written in red. You need to type in the same characters in the security pin column. The characters are case sensitive so please assure that you are entering it in the right case.
The security pin is same as the captcha that you might find on any other websites to ensure that you are not a robot but a legitimate human user.
If you are not able to find the security pin there, try checking your internet connection and refreshing the page. If that also doesn't help, you can visit the webpage after sometime. The problem may be because a lot of people are trying to access the link and there could be an internal server error. Hope it helps.