Can you get chickenpox from the sun's rays?

No, you cannot get chickenpox from sunlight rays. The varicella zoster virus causes chicken pox, it spreads mainly by touching or breathing in the virus particles that come from the blisters and also through tiny droplets from infected people.
Sun rays does not cause chickenpox rather it may prevent the spread Of chickenpox. It is known that ultraviolet (UV) rays can inactivate virus on the skin and make it harder to pass on.

However, it's not wise to stay under the sun during a chickenpox infection because the skin is more susceptible to being burned. Sun exposure will increase the risk of scarring. Too much heat and sweating, which can happen if someone is under the sun for long can cause itching for the infected person.