How to add the free/busy option to my events in iCal?

I have a shared iCal account for family use. When I create an event in that calendar (or any iCal calendar actually), I don't have the option to mark the time as free or busy. So, all-day events (e.g. Sam's Birthday) show the entire 24 hours as busy. This is very bad because it messes up my ability to use booking services. My entire day shows that I'm busy. The only options I have when creating an event are Event Name, Location, Date, Times, Alert, Repeat, Travel Time, Invitees, Notes, URL, and Attachments. What do I need to do to add the free/busy option to my events in iCal?

I reached out to Apple support and they leveled it up to the engineers but provided no solution. This is a big issue for running my business.

[Edited by Moderator]

Original Title: No free/busy option in iCal events