Hello,
.
To get admission in B.TECH you need to consider following eligibility criteria.
.
10+2 passed
Candidates appearing in class 12th or equivalent are also eligible
There's no age limit
Candidates can participate in exams 3 cousecutive years
It is necessary to have taken 5 subjects in class 12th and they are,
Language
Physics
Mathematics
And any one from chem,bio, BioTech,
.
If you are eligible according the following points mentioned you are eligible for  b tech.
For more details please visiting the following link

https ://engineering.careers360.com/articles/jee-main-eligibility-criteria

Please visit for more brief details.
Thank you