You unfortunately asked multiple questions which is against enotes regulations, so I have been forced to edit your question down to focus on the treatment of nature in this unforgettable poem. Please remember that enotes entitles you to ask only one question per day.
There is lots of critical debate about the presentation of nature in this poem, and there certainly seems to be a conflict between the man-made "pleasure dome" created by Kubla Khan and the raw, natural expression of nature as depicted in the "caverns measureless to man" and the "chasm." We can see Kubla Khan's act of creation as symbolically trying to "order" nature. Note how the poem talks about "girdling round" the land to create the dome, and ordering nature according to his desires. The image of the gardens, "bright with sinuous rills" and incense trees clearly presents an image of domesticated beauty and there is a peaceful, relaxing tone to this stanza.
However, note the change of tone in the second stanza as the poem moves to describe the "deep romantic chasm," which is a "savage" location. The imagery becomes frightening and the tone becomes sinister as the poem moves to describe nature. Note too that it is out of the "tumult" of the river that Kubla Khan hears the "ancestral voices prophesying war." Nature can be said to therefore be undomesticated, dangerous, unpredictable and terrifying in its power and might, and whilst Kubla Khan has been able to "tame" nature in his pleasure dome, the reference made to the caverns and the river and sea expresses the violence and sheer force of nature that cannot be tamed.
Of course, some critics argue that nature acts as a symbol for the force of the imagination and creativity, which can be harnessed in some ways to create works of art, is powerful, mysterious and inexorable and can never be fully controlled by human beings.