The ESP32-S3-DevKitC-1 is Espressif's entry-level ESP32-S3 board: Wi-Fi, Bluetooth Low Energy, and almost every GPIO broken out to two long rows of header pins, one down each side. It plugs into a breadboard or takes jumper wires, and you program it over USB.

The brains of the board sit in the module: a smooth, flat rectangle about the size of a postage stamp, soldered onto the end of the board opposite the USB ports. It has a small bite out of one corner: hold the board chips up with the USB ports toward you, and the bite is at the module's far right corner. That's the ESP32-S3-WROOM-1, and inside it are the ESP32-S3 chip itself, its flash and PSRAM memory, and the antenna. The antenna is the far end of the module, a sort of rectangle that hangs past the end of the board.

The MAX98357A is a tiny mono Class-D amplifier that takes digital I2S audio straight from a microcontroller and drives a speaker directly. You don't need a DAC, an analog input, or even an MCLK pin. It just needs three wires of I2S, power, ground, and a speaker. These are my notes on it, written so you can wire one up without looking at it, because I can't.

I'm using the Adafruit board (product 3006), but most clones use the same 7-pin layout.