Fluxbox, unlike KDE (Konqueror) or GNOME (Nautilus) does not have an integrated file manager. We have chosen Thunar as the TinyFlux file manager. Thunar was developed for XFCE, but works great in Fluxbox. You'll find that Thunar contains all the intuitive features you'd expect from a modern graphical file manager, including great support for removable media. Just click on File Manager from the menu to launch Thunar. You'll be taken straight to your /home directory from where you navigate around your filesystem.
You can open a terminal at any point by right-clicking in Thunar. It also has inbuilt support for extracting and compressing archived files.
You'll find you can configure Thunar using the Preferences option in the Edit menu. For more information on Thunar, try the Thunar website at this link.