Does Harper Collins take the writing from agents or do you need to write whole book and then give it agent send HarperCollins?

HarperCollins, like most major publishing houses, does not accept unsolicited manuscripts directly from authors. They only accept submissions from literary agents.

Here's how the process generally works:

1. Writing the Book: You write your entire manuscript, edit and polish it thoroughly.

2. Finding an Agent: You query literary agents, sending them your manuscript or a sample chapter with a query letter.

3. Agent Representation: If an agent is interested, they will sign you as a client, becoming your representative.

4. Agent Submission: The agent will then submit your manuscript to publishers, including HarperCollins, if they believe it's a good fit.

5. Publisher Review: HarperCollins editors will review your manuscript and decide whether to offer you a publishing contract.

In summary: You need to have your full manuscript completed and find a literary agent who will represent you and submit your work to publishers like HarperCollins.