Well I don't know what byte array stuff are
Binary data, it's what bitcoin uses. The hex code we always pass around is just a human readable representation of the binary data. A byte is a u8 which has a range of 0 - 255, and a private key has 32 of them.
What you described earlier, a 1 with zeroes behind it looks like this 000000000000000000000000000000000000000000000000000000000000000000000000000001 maybe "behind" means something different in your world, like front? Tell me, are you from the upside down world? Lol.
Ahhh, I think I see the misunderstanding. I'm going to take a guess that you're native language is not English?
000001 = zeros in front of 1
1000000 = zeros behind 1