Choice resources versus picklist and record choice sets
Key Takeaway
Choose the choice resource by where the options come from. Salesforce recommends using a Choice only when you can't use a Record Choice Set or a Picklist Choice Set.
In a screen flow, choice resources supply the options users pick from. You can build each option by hand as a Choice, or you can generate options automatically with a Picklist Choice Set, a Record Choice Set, or a Collection Choice Set. Your pick decides how much upkeep the flow needs and how much control you have over labels, values, and filtering.
Screen components that ask users to select from options
Flow Builder has four screen components that ask users to select from options. The Picklist and Radio Buttons components allow only one selection, but the Multi-Select Picklist and Checkbox Group components allow several. Most of these components need at least one choice resource, which defines the options users see.