Smart Watches KW76 User manual

Hello! I've reviewed the user manual for the KW76 smartwatch, which includes instructions for FCC compliance and troubleshooting radio interference. The document also shows a display of the watch interface. Feel free to ask me any questions you have about using your device.
What does it mean that device complies with part 15 of the FCC rules?

What should I do if the device causes harmful interference to radio or television reception?

Can I use the device in portable exposure conditions?