You can use the K87 out of the box without any software. The physical keys work, the default RGB cycles, and Fn-key shortcuts (e.g., Fn+Q to change Bluetooth device) are hardware-based. However, to disable the Windows key, change the polling rate to 1000Hz, or set a custom static color, the software is 100% necessary.
If the Ziyoulang-branded driver fails, many enthusiasts use the Womier/Gamakay K87 software , as they often share the same internal PCB and firmware. ziyoulang k87 software
The is the hidden engine behind one of the best value mechanical keyboards on the market. While it lacks the polish of Logitech G Hub or Razer Synapse, it is remarkably functional for a budget product. It gives you complete control over every key, every macro, and every LED. You can use the K87 out of the box without any software