USB-A Expansion Card
The Framework Mainboard contains 4 USB-C ports, but they're difficult to reach without an Expansion Card attached. If you're looking for other functionality such as USB-A, HDMI, DisplayPort, Ethernet, microSD, or audio you'll want to pick up those Expansion Cards in the Framework Marketplace.
This depends on your needs. If you're looking for networking functionality, all you need is the Cooler Master Mainboard Case, Framework Laptop 13 Mainboard, memory, USB-C power adapter, USB containing the OS of your choice and you're ready to go. If you're looking for a more traditional desktop PC setup, you'll need the Cooler Master Mainboard Case, Framework Laptop 13 Mainboard, memory, storage, WiFi or an Ethernet Expansion Card, USB-C Power Adapter and a display.