Adding custom date and time fields on cFolder page

Hello Experts,

We have a requirement, where we are looking to add a custom date and time field on the cFolder page.

User will enter a date and time and save this. Now after expiry of the entered date, we have to change the user's authorization from Write to Read only.

Please find the cFolder screen shot attached where i am looking to add the custom fields-

I am new to BSP, so any help/input here will be highly appreciated.

Thanking you all well in advance.

Regards,

Mrityunjai