Tableau Bridge is a free utility that lets you connect Tableau Online to your on-premises data sets such as excel files, or internal databases located in your network.
It does this by running an agent or service through a computer located inside of your firewall. Find out how to set it up on your laptop.
Full Documentation https://help.tableau.com/current/online/en-us/data_fresh_sync_section.htm
Join my Discord Server. https://discord.gg/shBuxXr it's a little sparse at the moment but hang in there.