how do I export all data for the whole site rather than just my personal account
@Maribeth-Wilson please add more information about your support request - the spam bot flagged your post because you are a new user and typed your topic too fast.
Are you trying to download data from a site you self-host, a site that is hosted for you or here at meta?
You can take a site backup in Admin > Backups. This includes all site data so you can do precarious upgrades or move to a new server.