a. Who wrote the codes for DNA? - Old Navy
Nobody. It's not that sort of 'code'. It's just nucleotides doing their thing. That vast majority of DNA 'code' is meaningless gibberish, filler, parasitic code and broken stuff.
b. When did humans become sentient?
Sentience is a property of most species of complex animals.
c. Why do we desire to create and repair and emotionally "connect?"
Because we are a social species whose speciality is big brains. The ability to connect with other members of our group is essential to our survival and chances of reproduction.
and literally thousands of other questions regarding life and all of its incredible diversity
Keep asking and I will keep answering.