There is no age limit to appear MHT CET Entrance Exam. As per the eligibility you should have minimum 50% aggregate marks in 12th standard examination (45% for SC/ST/OBC candidates). You should have completed your 12th standard or equivalent examination from a recognized board/university with Physics, Chemistry and Mathematics. You can check the further eligibility to apply for the exam with the given below link.

https://engineering.careers360.com/articles/mht-cet-eligibility-criteria

Good Luck!