Syncthing is a great program for file sync between devices.
When you set it up on a new device, it can sometimes be a bit difficult to find a folder that you have shared with the new device in the actual file system. The path might by default look like ~MyFolderName
That actually translates on Windows to C:\Users\SyncthingServiceAcct
So go into that folder and you will be able to find your SynchThing files!