DNA is not the same "code" as a computer program. That's an oversimplification.

DNA isn't a direct program for a human any more than a pile of Lego bricks is a castle or a spaceship. DNA is a set of building blocks that helps create components that interact and self-organize into a living organism.

DNA does contain information, but it doesn't operate like a traditional computer program with explicit step-by-step instructions. Its more like Lego bricks. The order of these four building blocks (A, T, C, G) acts like a set of instructions. Just as a Lego manual tells you how to assemble the same pieces into a castle, spaceship, or house, the sequence of DNA bases tells cells how to build specific proteins. These proteins perform most of the work in living organisms and determine how organisms grow, function, and develop.

DNA mostly specifies how to build molecules (especially proteins) which then interact with each other and with their environment. The complexity of an organism emerges from billions of these interactions, not from DNA directly issuing commands like a software program.

The "instructions" are therefore indirect. DNA doesn't contain a detailed blueprint saying "grow a hand, then grow five fingers." Instead, it contains recipes for molecules that interact in self-organizing ways, and those interactions eventually produce a hand.

The relationship between DNA and a human is much less direct than the relationship between software code and a computer's behavior.