According to our current understanding of physics, an object with zero mass, such as a photon (a particle of light), travels at the speed of light in a vacuum and cannot accelerate to a speed greater than that. The speed of light in a vacuum is approximately 299,792 kilometers per second (or about 186,282 miles per second).
Since an object with zero mass is already traveling at the speed of light, it does not require any time to reach that speed. It is important to note that, from the perspective of a massless object like a photon, time does not elapse. This phenomenon is a consequence of Einstein's theory of relativity, which states that as an object approaches the speed of light, time dilation occurs, and from the perspective of the object, time effectively stands still.
So, for a massless object like a photon, it would not experience any passage of time during its journey at the speed of light. However, from the perspective of an observer, the passage of time would still occur. The implications of traveling at or near the speed of light, including time dilation and length contraction, are complex concepts described by special relativity and would require a detailed understanding of the theory to fully comprehend.
It's worth noting that objects with non-zero mass, such as particles with rest mass, would require an infinite amount of energy to accelerate them to the speed of light. As a result, according to our current understanding, it is not possible for objects with mass to reach or exceed the speed of light.