Is /proc directory generated dynamically per request?

So I am supposed to achieve following behavior.

This project you are asked to add a new field to the task descriptor. The name and type of the field is: int casper;

• If casper=0 : The process is visible to all, i.e. it is listed in the /proc file system and it can be seen using “ps”, “pstree”, “top”, ...
• If casper=1 : The process is visible only to processes which have the same user id, i.e. for all other processes, it is NOT listed in the /proc file system and it can NOT be seen using “ps”, “pstree”, “top”, ...
• If casper=2 : The process is visible only to processes which are in the same group, i.e. for all other processes, it is NOT listed in the /proc file system and it can NOT be seen using “ps”, “pstree”, “top”, ...
• If casper=3 : The process is invisible for all, i.e. it is NOT listed in the /proc file system and it can NOT be seen using “ps”, “pstree”, “top”, ...

I have already modified task_struct definition and its default value for init process and added necessary stuff to fork sys call

I did some research but couldnt find an obvious way to do this. So I assumed that /proc is created per request so I can get the task_struct of the process that requested it and populate the /proc according to that. Am I on the right track?

Yes, it is. /proc is a virtual filesystem generated by the kernel upon request. Check the following article for more details: Linux VFS