Hi Abhay,

Yes, if you have got 68% in 12th CBSE , and you got 74 percentile in JEE Mains and you are from OBC-NCL, you are eligible to register in JoSAA, though you will not get any result out of that as you will not be able to fetch a seat in any of the participating institutes like NITs, CFITs etc.

Refer here for more info - https://engineering.careers360.com/articles/josaa-counselling

To know your other best admission possibilities of Institutes & branches in JOSSA & State counseling as per your percentile, You can use JEE Main College Predictor tool given below

https://engineering.careers360.com/jee-main-college-predictor?icn=QnA&ici=qna_answer

Feel free to ask doubts in the Comment Section.

I hope this information helps you.

Good Luck!