What happens during the first step in DNA replication?

It starts when a protein starts the unwinding of the DNA helix. Next comes the separation of the DNA strands right before the transfer of genetic data to the newly assembled DNA strands starts. A protein known as helicase is what breaks down the hydrogen bonds between strands of DNA during replication.

The first step in DNA replication is the separation of the two DNA strands that make up the helix that is to be copied.