CircuitPython board.  This guide focuses on the ESP8266 and Feather M0/SAMD21-based boards, but any CircuitPython board that supports I2C should work.

If your board doesn't come with CircuitPython running on it already then check out your board's guide for how to load CircuitPython firmware.  For example the Feather M0 express guide is a good reference.

If you're using a Feather board and FeatherWing you probably want a Feather female header set or Feather stacking female header set.

PCA9685 DC Motor & Stepper Driver Board.  If you're using a Feather the DC Motor & Stepper FeatherWing is the perfect option.  The DC Motor & Stepper Arduino shield is another option that can be used with an Arduino form-factor board or on its own as a breakout for other boards.

For DC motors that are 'noisy' you might need to solder on small 0.1 microfarad decoupling capacitors, see this note from the motor guide.

Power Supply.  To power motors or steppers you need an external power supply.  Motors can pull a lot of power and could damage your board if powered directly from it!  Check your motor or stepper for the exact voltage that it requires--some motors only need 5V while others might need up to 12V.

DC or Stepper Motors.  You'll want DC motors which can move continuously at different speeds, or stepper motors which can move in precise increments.  Check out the motor selection guide for more details on DC and stepper motors.

Breadboard and jumper wires.  If you aren't using a Feather and FeatherWing you'll need a breadboard and jumper wires to connect the components.

Soldering tools.  You'll need to solder headers to the boards  Check out the guide to excellent soldering if you're new to soldering.