Rather,they should learn the science, not the beliefs creationists have about evolution.
It's a good idea for creationists to learn more about science, but for example, the AiG beliefs about vestigial organs blind them to what the term actually means.
"Vestigial" does not mean "useless." And it never has. Darwin, for example, pointed out that many such organs retain some functions or gain new ones. The appendix in humans does not serve as a fermentation chamber, as it does in some other mammals. but it retains it's function as a source of immune cells, and as a "refuge" for useful bacteria, when the flora of the rest of the gut is disturbed.
Likewise the AiG argument for "common designer" falls apart when they confuse homology with analogy. By that standard, we would expect bats and birds to be more alike then bats are to mammals. But the opposite is true.
And we know DNA relationships show ancestry, because we can check organisms of known descent.