That phrase means exactly what it says, so no, it's not an idiom.
In a solar eclipse, the moon comes between the sun and the earth so that the sun is blocked out. A lunar eclipse is when the earth comes in between the moon and the sun so that the moon is blocked out.
Nothing. The correct idiom is "get OFF your high horse," meaning stop acting so conceited as if you are above everyone else.
your fat mom blocked the dame sun so it blow up
This is not an idiom. Idioms make little or no sense unless you know the definition. This sentence makes perfect sense, so it is not an idiom. The dead fish smelled so bad that even as high as Heaven, you could smell them.
the moon covers the sun so from earth you cant see the sun.
No, an idiom is a phrase that makes no sense unless you know the definition. This makes perfect sense, so it's not an idiom. It is a proverb teaching you to do things when the time is right and not wait.
Getting on your high horse means that you are looking down on someone with a haughty or superior attitude.
Because the sun is blocked out, so it is like night, but it is not totally dark. When the sun is out it is too bright to see the stars.
"Get off your high horse" means to stop being so prideful and full of your self.
No, the idiom is actually "make hay while the sun shines". It means to do something when the conditions are right or optimal. Example "I have enough money to buy an investment property, so I may as well make hay while the sun shines." The idiom arises from the fact that hay is dried grasses, and in the past (and even today in some places) these grasses were/are sun dried, and the best time to do that, obviously, is when the sun is shining.
"Larger than life" is an idiom, so there isn't an idiom for it.
There isn't an idiom called "high fore." Try to figure out exactly what you heard or read, and type in another question so we can answer it.