Yes you can as you are giving 12 boards again in 2020. No matter if you have appeared in past using another board marksheet of 12. If give 12 again in 2020 and passed you will 2 attempts for adavnce i.e in 2020 & 2021 & 3 for Mains upto 2022. Good luck.

Hello,

if you want to appear jee advance then you have to appear jee main. Without jee main , you can't appear jee advance exam.

as you said you passed your +2 in 2018 which means 2020 is your last chance, you can't appear jee exam any more.

To give jee main 2020 , you have to satisfy the eligibility criteira of the exam.

1. Should have passed +2 in 2018,2019 or those who will pass in year 2020.

2. no age limit but has to satisfy No. 1 condition

3. Only 3 attempts.

if you have appeared jee main before then you it might be atmost 2 attempts as your passed +2 in 2018. so you can appear now. If you registred for january session then you should prepare for it. If you haven't registered then you can register or april session for which the application form will open in Feb end week or March.

prepare accordingly considering all the facts and must satisfying the criterias.

For more details you can visit the NTA official site

Hope it helps!