This is an example of a introduction paragraph that I did for an essay a few months ago. The book was Farewell to Manzanar.
In the book Farewell to Manzanar, Jeanne Wakatsuki Houston goes through several emotional and spiritual journeys that lead her to her identity. There is also a forced physical journey, but it is the reason for the journey and the things that happen along the way that help Jeanne learn about herself.
The prompt for this was:
What does this literary work reveal about one or more characters’ quest for identity, in terms of the type of journey or journeys, physical and spiritual/emotional (external and internal) they go on and what they learn about themselves and others along the way.
In this first paragraph I address several key ideas described in the prompt. I say what book it is in, and who I will be writing about from that book. I say what kinds of journeys she undertakes, and specify which journey it was that I believed helped her learn about herself. Often, this is the hardest part of the essay to write, and because of that, I often write my body paragraphs, then go back and write this based off of them.
Bottom line: This paragraph should tell the reader what you will be talking about and what you are going to say.