How to automatically sync local files with Teams?

How do I automatically update the files on teams with the files I've worked on locally on my computer? Based on how I understand Teams, it seems like I have to manually upload & replace every file into the various locations in my Teams file structure, which is a pain. Is there a better way to accomplish this? What am I doing wrong? I tried the "sync" feature on the Teams taskbar, but that didn't seem to do anything.