How to examine if there is termite damage in a ceiling or floor using a boroscope

A horoscope will do you no good here but a borescope may, or may not depending on the severity of the damage.

Generally the best you can see with a borescope is EVIDENCE. Wood debris in the area below the infestation, mud tubes between the ground and the wood, possibly some areas in wood where chunks have fallen off. But seeing direct termite damage is iffy.

The problem is that they enter through very small holes, which may not be in a visible area and eat away from the inside. They generally don't penetrate to the outside to protect themselves and so the wood piece can look perfectly fine from the outside and be riddled with damage on the inside.

Usually you use a "poking" tool to check for such damage although cutting will expose the damage as well.