This is possible. But keep in mind, this is NOT what Excel is good at. You can write a macro to hide/unhide sheets based on a person's id. But if a person has VBA skills and Google, they would likely be able to hack it open. My advice.... if you don't want a person to see the data, do not send it to them.

Instead, maybe write a macro that creates 30 different workbooks based on what you want/don't want each person to see??