Yes. You must carry car insurance. The state of Wisconsin requires that drivers carry liability insurance of $25,000 minimum, $50,000 for accidents involving injuries/deaths of more than one person and $10,000 for property damage per accident.
The documents that you will need vary depending on the insurance company to which you apply. Generally, insurance companies want you to submit proof of your identity, your driving record and information about the vehicle you would like to insure.
There are limitations on your license after you receive it initially. For the first nine months, you are only allowed to drive with one passenger that is not a family member and you are not allowed to drive between the hours of 12 AM and 5 AM.