In the discussion of this issue, the most important place is occupied by the Special Theory of Relativity (SRT). According to the conclusions of this theory (which are currently well confirmed by experimental facts), when an object moves at the speed of light, an arbitrarily long period of time for this object becomes equal to zero.
It is important to note that any period of time, even billions of years, for an object accelerated to the speed of light, will turn exactly to zero, and not to an infinitely small period of time. And what does it mean if the time interval turned into zero?
This means that no action is possible, including observation, seeing, and so on. Thus, an object flying at the speed of light will not see anything. In general, this object is actually not even aware of the fact of its existence, and the existence of the world around it, because this also takes time. Although relative to the Earth, for example, this object will exist for itself, and it is possible to travel at the speed of light for a very decent period of time.
Photons are such objects that, from the moment of their emission to the very absorption, fly only at the speed of light, i.e. they do not waste time accelerating and decelerating, so their whole life for them lasts zero time. Thus, the world through the eyes of a photon is as follows: the coinciding moments of the birth and death of a photon do not give him the opportunity to “understand” that the world exists at all.
Let's note one subtlety: the captious reader could note that so far I have avoided the question of what the object must move at the speed of light relative to in order for all this to become true. But this question does not really matter, because according to the basic postulates of SRT, if an object has already accelerated to the speed of light relative to at least one frame of reference or a body, then its speed in all frames of reference becomes equal to the speed of light.