この文の文法の構造を教えてください。

英語が変です。

This entertainer, who revolutionized show business, was in to shock, rather than amuse, the audience.

ひょっとしたら、話し言葉を機械の音声認識で文字にしたために、間違っているのかもしれません。上の文を２つに分けると次の通り。

This entertainer revolutionized show business. He was in to shock the audience, rather than amuse them.

This is not a piece of advice to you I'm talking to myself for my practice of writing skills.
I suppose the word 'revolutionized' is the past tense form of the verb 'revolutionize'.

This is not a piece of advice to you I'm talking to myself for my practice of writing skills.
This entertainer (who) revolutionized show business were in to shock rather than amuse the audience.
1)This entertainer: subject
(who)
2)Phrases that modify the subject: revolutionized show business
3)verb: were
4)prepositional phrase: in to
5)object: shock
6)adverb phrase: rather than
3)verb: amuse
5)object: the audience