Question

Hello Rabbi,
I wanted to ask about the Festival of Sukkot. More specifically: what is the significance of the sukkah, the four species, the water libation, sitting in the sukkah, eating in the sukkah, the height limit of twenty cubits, and the ushpizin? And is there one idea that ties them all together?
As stated, the festival is very unclear to me, and I would be glad if the Rabbi could clarify as many aspects of it as possible.