It's useful, if a bit circular, to think of each dimension as multiple instances of the dimension before it.
No. Completely and utterly wrong.
Look into the concept of linear independence.
In short, a vector in a vector space can be described as linear combination of the space's base vectors. If you wish to add another dimension, you'll need to add another base vector, which is linearly independent of all other base vectors - you cannot describe the new base vector with the existing ones.
Example:
Let's say you have base vectors [1, 0, 0] and [0, 1, 0]. You can describe any vector in that plane as a combination a * [1, 0, 0] + b * [0, 1, 0], where a and b are scalars.
Now you add another dimension with a base vector [0, 0, 1]. You cannot chose any real a and b, so that a * [1, 0, 0] + b * [0, 1, 0] = [0, 0, 1]
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Edit:
Look, I get it people. You love thinking about the universe and in general, things you lack knowledge about. But the first idea you come up with is not necessarily the truth. There's also a high probability that what you're wondering about has already been answered, but let me make this clear:
You will not find it on Wikipedia.
Wikipedia has become the dumping ground for wild and whacky theories about everything, without providing a proper context and mathematical explanation. You'll find everything from hypothetical particles to multiple universes, but you won't find a good Math and Physics course. If you really want to know more about the subject, look for university courses that ended up online.