Using Mobile Data in the USA

Hello!
I will be traveling with my family to USA for three weeks. I am looking for some guidance about the use of mobile data when we are there. In Belgium we use Orange, which has a package of 1 GB for EUR 20. I am wondering if there is a better option. One suggestion has been to get a prepaid card from the US, but I am not sure how to go about that. Thanks in advance.