Whilst it is possible to move files within Teams, it is not immediately obvious how to move folders. Moving a Teams folder is not possible directly from within Teams, but can be done from Sharepoint or File Explorer. File Explorer is the easiest, most intuitive way to achieve this, so that technique is described below
Firstly, make sure that Teams files have been synchronised with File Explorer as described in the following document:
Once this has been done, Teams folders can simply be moved by dragging and dropping as for normal files and folders.