Returning Multiple Column Headers based on cell values

Hi,

I am arranging schedules for multiple students and have an excel file that has the class names along the top, student's names along the side and a matrix of confirmed/blank.

I want to be able to enter a students name and have all the classes they are taking (column headings) returned in a list.

I am totally stuck - I wrote the following but it only returns the first class that is confirmed, while I need all of them.

=INDEX(Classes,MATCH("Confirmed", INDEX(Confirmation,MATCH(C31,Name,1),),0))

Example worksheet attached
I have Excel 2016 but not 365.

Thank you!!

Amazing, thank you. I'm relatively new at excel, if it is not too much to ask would you mind explaining how it works so I could do it myself in the future?