How do I edit/change Custom Fields (ex: add dropdown box) and move the field around the form? When I click on Edit everything is shadowed and I can't change anything.

Hi, @sherry20. It's great having you again in the QuickBooks Community. 

If you're in QuickBooks Online (QBO) Advanced, you can only change the name and select or deselect the forms when editing a custom field, and moving around the custom field around isn't currently possible. However, I can suggest a couple of alternative options.

Aside from editing a Custom Field, you can consider creating a new one. You can follow these steps: 

1. Go to the Gear icon.
2. Select Custom fields.
3. Click on the Add field tab.
4. Enter the necessary details and from the Data type drop-down list, select Dropdown list.
5. Hit on Save.

Regarding moving the custom field around the forms, the custom field is typically located at the header of your sales forms and you can choose to edit the type of template to change its placement.

1. Go to the Gear icon. Then, Custom form styles.
2. Select New style and choose the type of sales form.
3. From the Design tab, select Change up the template.
4. Edit other necessary details and click on Done.

However, if you use Essentials or Plus, we can only add a custom field to all sales forms and creating a dropdown list isn't possible to both the subscriptions.

If you also want to make changes to your sales forms after this, let me add this article as a reference: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Let us know if you have further questions about editing custom fields in QBO. We'll do our best to assist. Take care.