Update sql server from a dataset

Question

I have code that is designed to select four columns from a table on my sql server database then populate two of them with information from the internet and then update the database with the data from the newly populated columns. I can do all of this except the updating the database.

Current Method: 

create sql connection and use select command to get data from database

use dataAdapter to fill a dataSet with the result of the select command

populate columns based on web data and save changes to dataSet

???? how do i put this data into the database from the DataSet