Hi @Aaron Wolff ,
You could use SharePoint Migration Tool (SPMT) to migrate files to SharePoint online.
1.Start a new migration
2.Click File share
3.Choose your folder, remember to check "Migrate selected floder and folder contents" option
4.Select Copy content to SharePoint
5.Type your site url
6.select library you want to migrate to
For Reference: Install the SharePoint Migration Tool (SPMT)
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