Hi, To customize existing dropdown fields in Dynamics 365 Sales, follow these steps:
Navigate to the "Customizations" area in Dynamics 365 Sales.
Select "Entities" and then choose "Opportunities".
Click on "Fields" and find the dropdown field you want to customize.
Double-click on the field to open its properties.
In the properties window, you can customize the values in the dropdown by selecting "Options" and then adding, editing, or deleting values as needed.
Save your changes and publish the customization.
That's it! Your customizations to the dropdown field in Opportunities should now be in effect. I hope it helps.