Permission level:  Entity Administrator 

1. Click on Building Icon > Business Entity > Manage Setting > Application Forms

2. Click on Manage Fields 

3. Click on desired input field section (e.g. Nationality)

4. To make the input field compulsory, click on * icon - to hide the input field, click on the X icon; and to make the input field optional, simply select the tick icon

5. Click on the Save button to update your application form template