Meaning of 纸 in radicals
According to the question, you should only need to describe the radical (found in this case as the left hand component) 糸, not 氏.

The word 部首 is literally translated as section header, and strictly refers to the header under which the character is grouped in dictionaries. Each character has only one 部首, just like each English word has only one first letter under which they are found in dictionaries.

If your teacher also asks you to describe 氏, then that should be done in a separate question; if they think that 氏 is a 部首 in the character 紙, then they are unequivocally wrong. 紙 is a semantophonetic (形聲) compound character under the traditional liushu scheme of classifying characters. You can only refer to 氏 as a 聲部 (sound component) in 紙, not a 部首.

最早"紙"是什麽意思 (punctuation added) is asking you to find out what 紙 meant in its first appearance in historical literature. This may be trying to get you to appreciate that many characters have changed meaning over the course of history.