I am creating the form and under 1 form , when someone select
Option 1 or 2, the form should get change , for e.g when student received the link , and they select standard 5 or 6 , lets say he select 5, the form will be different and 6 will be different
It sounds like you are looking for conditional logic in forms, whereby selecting an value or option in one form field then hides, shows, or changes, subsequent form fields.
This is not available today, however, it is on our roadmap for the next round of Forms improvements. Stay tuned to our feature announcements.