Sunlight can transform into heat energy when it enters matter. When sunlight hits an object, it can be absorbed by the object and transformed into heat energy. The amount of heat energy produced depends on the amount of sunlight absorbed and the properties of the object, such as its surface area, color, and material.
Sunlight can also produce heat energy when it reflects off matter, but in this case, the heat energy is produced by the reflection itself rather than the absorption of sunlight. For example, when sunlight reflects off a shiny surface, it can produce heat energy due to the friction between the light and the surface.
Sunlight cannot produce heat energy when it cannot reach matter or when it travels through space. In these cases, there is no object for the sunlight to interact with, so it cannot be absorbed or reflected and therefore cannot produce heat energy.