If you want to apply for architecture you should appear for JEE and NATA exam.

You can also check the eligibility criteria of both the exams below

JEE Main

- You should be born on or after October 1, 1993 are eligible to apply for JEE Main 2018. There is relaxation of age for reserved category student for 5 years.

- You must have passed 12thclass or qualifying exam in 2016 or 2017. Appearing students can also apply.

- It is mandatory for candidates to have taken 5 subjects in 12thor qualifying exam.

The 5 subjects for B.Arch/ B.Planning are:

1-Language, 2-Physics, 3-Mathematics (compulsory), 4-Any one of (Chemistry, Biology, Biotechnology, Technical Vocational Subject), 5-Any other subject.

- To take admission in NITs/IITs/IIITs you should have 75% marks in your board exam or you should be in top 20 percentile. For SC/ST you should have 65% marks.

- You can only attempt JEE Main 3 times.

To check the complete eligibility criteria you can refer below link

JEE Main Eligibility Criteria

NATA

You should have minimum 50% marks in class 12th  with mathematics as compulsory subjects.

To check the complete eligibility criteria you can refer below link

NATA Eligibility Criteria

Good Luck!!