You can check the details below

1- JEE Main- Application form for JEE Main will be released on December 1 2017 and last date to apply for application form is January 1, 2018.

2- VIT- The online/offline application form of VITEEE 2018 can be submitted till February 28, 2018.

3- SRM- You have to submit the application form on or before March 31, 2018 which is the last date for application filling and submission

4- Amrita- last date for filling application form  is March 31, 2018.

Top check the information for all the entrance exams of engineering you can refer below link

https://engineering.careers360.com/exams

Good Luck!!