Hello Arvind,

Refer the link to get information :

https://medicine.careers360.com/articles/neet-eligibility-criteria

https://medicine.careers360.com/articles/neet-eligibility-criteria

From this you can get all the information

Hope I helped you.All the best for future endeavour!!

If you took admission in 2018 in 11th standard, it means you'll take admission in 12th class in 2019 (ideally). You'll pass 12th in 2020 (ideally), which will make you eligible for AIIMS 2020. Hope this helped. Good luck.