i got 18887 in jee mains can i get ece or cse in south NITS or IIIT open category rank:67902,category rank:18887 Obc category

Hello aspirant,
With your quoted details it's hard for you to get any NIT or IIT Except if you are having one in your home state as it demands for rank under 10,000 for your category rank.
You can try to go for some descent GFTI's .
Here below I am providing a detailed cutoff analysis link -
cutoff for NIT's
cut-off for GFTI's

You can also predict your future college on basis of jee main score using the link given below-
https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

I hope this helps.
Regards
Madhur