If I got in a car accident and it was a lien put on me from American family insurance, what does that mean?

No one can put a lien on a human being-at least not since slavery was abolished in the US in December 1865. However, if someone wins a judgment against you, and properly dockets it, in most places the judgment becomes a lien (which means a kind of claim against property) against your real estate for a period of years after the docketing in any county in which the judgment is docketed. It can extend to new real estate you acquire during the period when the lien is valid (in Wisconsin it's ten years). In Wisconsin, if you get a discharge in bankruptcy, your lawyer can file an application in state court to have the lien deemed satisfied. (Hiring a skilled lawyer is almost always worth the effort.)