Hello sophiabickford18,
Computers are usually categorized as Other business expenses or Business assets. These categories are are still reported on your Tax Summary or Tax Details. You can refer to this link for more information: QuickBooks Self-Employed Schedule C Categories breakdown.
Meanwhile, we won't be able to give you an advice whether you write off the laptop from your tax deductions or not. However, you can use this link as you guide on how to categorize your transactions: Working for yourself.
It is also best to contact HMRC for their advice about your concern. They know what's best for you and your books.
We'll be right here of you have additional questions. Have a great day!
