There's a K-1 fiancée visa, which authorizes you to be in the U.S. for 90 days to get married and file a Form I-485, Application to Adjust Status, to become a permanent resident.
Theoretically that entitles you to a 90-day employment authorization document, but in practice it takes 90 days to get the card, it's worthless. You won't be authorized to work until about 90 days after you file the Form I-485.
So if your main concern is work authorization, then you can either apply for the K-1 fiancée visa before marrying or the spousal immigrant visa after marrying. Of course, there are other issues to consider in deciding between these two visas (e.g., timing, filing fees, whether you prefer to marry in the U.S. or abroad, etc.)