Zephyr Workbench, a VSCode extension to manage Zephyr on STM32.
It enables users to easily create, develop, and debug Zephyr applications.
Main features:
Install host dependencies.
Import toolchain and SDK.
Create, configure, build and manage apps.
Debug STM32.
You can directly download it from the VSCode marketplace
For more details, visit the Zephyr Workbench
All your needs are in the STM32 Cube Firmware packages
For example, If you are using STM32F4 you need to download STM32CubeF4 from ST website and look for I2C examples within the downloaded archive.