The adapter you need is Apple’s US$49 Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter.
Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter
At least this pricey adapter is bi-directional. That means you can use it to connect a Thunderbolt 3 device to a Thunderbolt 1 or Thunderbolt 2 port on an older Mac.
How to connect an external display
This one can eat up a chunk of your budget, because there are so many different types of display connectors. Be prepared to buy several adapters.
DisplayPort and mini DisplayPort
To connect to a DisplayPort display, you need a USB-C to DisplayPort cable or adapter. Amazon sells the Plugable USB-C to DisplayPort Adapter cable for US$20, and it supports 4K video at 30Hz.
Plugable USB-C to DisplayPort Adapter
To connect a display with mini DisplayPort, you need an adapter like the Allsmartlife USB C Type to Mini DisplayPort/Mini DP Adapter Cable (US$17 on Amazon).
Apple offers the USB-C Digital AV Multiport Adapter, a US$69 device that also provides a USB-A port and a USB-C port that’s for charging only.
Apple USB-C Digital AV Multiport Adapter
If you don’t want to spend that much, you can get an adapter that’s just USB-C to HDMI adapter, such as Aukey’s USB C to HDMI Adapter (US$20 on Amazon). When shopping for such adapters, look out for 1080p support.
To connect a VGA display, Apple has a USB-C VGA Multiport Adapter for $69. In addition to a VGA to USB-C connection, it also provides a USB-A port for connecting a USB device, and a USB-C charging port to keep your laptop battery happy.
More on the affordable side but without the USB ports is the Belkin USB-C to VGA Adapter, which is available on the Apple Store for US$40.
How to connect the MacBook Pro to ethernet
You’ll probably use Wi-Fi most of the time, but using a wired ethernet connection has its advantages. To connect to an ethernet network, you need an adapter like the Belkin USB-C to Gigabit Ethernet Adapter, which is available in the Apple Store for US$35.
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