Web Platform / App -
When you click on the icon at the top left corner of the screen, go to My Section ----> All India Tests ----> here you can view your live exams, upcoming, attempted and missed exams. For the live exam click on start button and attempt your exam.
Web Platform / App -
On the home page, click on the study tab -----> change exam -----> click on add more exams -----> select the respective exam categories -----> Choose your main exam ----> Done.
Based on the exams selected, all AITs related those will be displayed under All India Tests section.