Hi aleesha_m-yahoo-,

Thanks for posting in the Community!

When you create the expense transaction make sure to use the Item details section to be able to add the raw materials in QuickBooks Online. 

If you have created an expense transaction and wanted to add to a projects. You can check the steps here:

1. Go to Expenses, then Expenses.
2. Find and select the transaction you want to add to your project.
3. In the Customer / Project column, select the ▼ dropdown, then select the project you want to add the transaction to.
4. Select Save and close. You may also select other save options.

You can refer to this link to learn more about: Create and manage projects in QuickBooks Online and Accountant.

Post again in the Community if you have further concerns about projects. I'll be around to help you.