I didn't know this. I did my hunter's safety course in Ohio about 40 years ago. Indiana has never asked to see proof.
As stated above, you are old enough for it not to be required. I wasn't required either, but took a neighbor kid to the DNR hunter safety course 20 years ago. It was well worth the time and very informative. The class even opened my "seasoned hunter" eyes to some different perspectives on handling firearms safely.
I wasn't aware that the hunter safety classes can be taken online. I hope they have the same effect as the in person class we took? Numerous "opossum cops" and a range safety officer from Hoosier Hills rifle and pistol club conducted it.
.