The Radio Buttons field picks one option among a few, all visible at once.

Configuration
Go to Modern Fields > Fields groups and add the Radio Buttons field. Its settings are in the inspector:
| Effect | |
|---|---|
| Radio buttons layout | Vertical or Horizontal. |
| Values | The choices offered. Each option has a label, shown to the user, and a value, which is what the field stores. Each value must be unique: the settings panel flags a missing or duplicated key, and only the first option with a given value is displayed. |
Display the value
The field stores the value of the selected option. Read it with get_field():