Salesforce has a field type called picklist. It is similar to what the web normally refers to as a dropdown list. Donorbox has the ability to export to a Picklist field, but there is one important caveat: the picklist field values between Donorbox and Salesforce must match.
Assuming, you have a picklist in Salesforce in the opportunity object by the name of Payment Method. The most obvious matching for the SF Payment Method field is the Donorbox's Donation Type Field. You can map it from https://donorbox.org/org_admin/salesforce_settings/new.
Please note that the Donorbox's Donation Type field has these possible values: stripe, ach, paypal_express, cash, check, and credit_card.
For the export to work, the SF Payment Method Picklist field must accept these values as well. For more details regarding data mapping, please look at our data mapping guide: https://donorbox.org/nonprofit-blog/salesforce-data-mapping-guide/