[Harri (OP)]

The sun rises and covers half of the earth in sunlight. When I look into the night sky once the sun has set I see thousands of stars. If I look at a star the size of our sun in the night sky, what happens to the light it emits that results in it being just a pinprick by the time it reaches my eye?

[Bored chemist]

This is actually a more interesting question that it first seems.
The fact that it gets dark at night offers a profound understanding of the Universe.
The fact was considered  a long time ago and there's  a pretty good summary here

https://en.wikipedia.org/wiki/Olbers'_paradox

[evan_au]

If I look at a star the size of our sun in the night sky, what happens to the light it emits that results in it being just a pinprick by the time it reaches my eye?

Let's for a moment ignore the important questions raised by Olbers' Paradox, and just consider our nearest 5 stars....

The visual height of an object on my retina halves every time I double the distance.
The visual width of an object on my retina also halves every time I double the distance.
The visual area of an object on my retina reduces to 1/4 every time I double the distance (area ≈ height x width).

Our nearest Sun-like star is Alpha Centauri A.
- It's diameter is 1.1 times the diameter of the Sun
- It's distance is 4.4 light years, compared to 8.3 light minutes for the Sun.
- So the diameter of Alpha Centauri A as seen from Earth would be 300,000 times smaller than the diameter of the Sun.
- And the area of Alpha Centauri A as seen from Earth would be 80 billion times smaller than the area of the Sun.
- If you had a big enough telescope to see a visible disk at all!
- That's a pretty small pinprick...
See: https://en.wikipedia.org/wiki/Alpha_Centauri

For a glowing object like a star, the brightness reduces to 1/4  every time I double the distance; this is called the "inverse square law".
See: https://en.wikipedia.org/wiki/Inverse-square_law

[alancalverd]

In short, the other stars are a lot further away.

[Bored chemist]

Or, equivalently. much more of the light from the other stars misses your eye.

[myuncle]

Or probably the OP is asking: if the light travels and never stops, why it gets dark at night? And why can we actually see the stars during the night? Maybe a simple example is all is needed. You are in the dark at night, your friend has a torch, you stop, and your friend keeps going, his torch will get smaller and smaller, until you can't see the torch anymore. Why? Not because the light of the torch doesn't reach you anymore, but because only a portion of that torch is going to reach your eye, and that portion is so small that you can't see anything at all. Same way, only a tiny patch of the stars light actually hits our eyes, otherwise they would blind us.

[Halc]

Olbers' paradox says that no matter how far and small a star gets, if you look in any random direction, you should eventually hit a star, or planet or something.  There should be no path that is not eventually obstructed by something, and that something has a far greater chance of being as bright as the sun as it has of being darker like a planet.
So the night sky should be nearly as bright as the sun, and should thus not be night at all.

The answer, as pointed out in the link, is that while it is indeed true that a typical line of sight ends at a star, that star is moving away from us at some insane speed and has red-shifted its light into darkness. That, and the fact that the further you look in distance, the further back in time you are looking, and far more than likely that the star that obstructs your view is so far away that light from its first ignition has not yet reached you.

Both effects (redshift and young age) are evidence of a dynamic universe that is respectively expanding and finite in age. In the static universe as envisioned by Newton and others (yes, even Einstein), the sky should indeed be uniformly bright in all directions.