Hi @sml929,
Which Dropdown you used to choose the value, is this DropDown control together with the EditFrom control in the same screen?
And it would be much helpful if you could share a screenshot.
Besides, have you checked the following article?
Understand data forms in Microsoft PowerApps
Which is helpful if you are working with form controls.
For the EditForm control, New record mode, if you would like to configure the DataCard default value to the Dropdown.selected value, two properties need to be configured with the corresponding field:
Default property->Dropdown.Selected.FieldName
Update property->Dropdown.Selected.FieldName
Regards,
Michael