How might advertising lead young people to make poor choices?

Like the last person said, it can influence them. Say its an ad for vape. They might say "oH itS nOt LiKe SMOkiN!" (Even though it is) but a naive person might believe it and start vaping/smoking which is a poor choice and can harm them.

It probably influences them in the wrong way effects them maybe for the rest of there life, depending on the ad.