Ender 3/Ender 3 Pro /Ender 3 V2 (32-bit Motherboard)
Video shows Ender 3 V2, but the firmware installation process is the same.
Firmware Files can be downloaded on https://www.creality.com/download. Select the correct .zip file according to your motherboard version number and flash the .bin file with the phrase "With Adapter Board" in it's name.
For a more in-depth guide on how to use the BL Touch after installation, such as setting z-offset, please read: https://www.makersupplies.sg/blogs/tutorials/how-to-use-bl-touch-on-ender-3-v2-after-installation