Hello, Sierra. I think I can help. When DNA makes a copy of itself (replicates), it opens up and each side of the DNA helix pairs up with loose nucleotides that have specific nitrogen bases. Adenine only pairs with Thymine and Guanine only pairs with Cytosine.
In your question, you only show one side of the DNA helix. Was there another strand too? If not, You will show how the specific nitrogen bases can just pair up in the correct order.
A always with T
G always with C
Since your strand is in the order below, the nitrogen bases would match up in this way:
Do you think you can finish it now? Hope that helps.