How to find a record from an index number?

Hello! I'm a new member and I'm finding this website overwhelming. I've watched a couple of videos but still don't know where to search for a birth record based on the index number?

I found the birth record index number for Joseph E Feest, b. 1 Sept 1937 which is 62012. How do I use this to find the birth record itself?

I've also searched for his name in the search fields and got no hits. Same with his father, Otto Henry Feest, b. 16 May 1912.