
Explanation

Box 1: Choice
Like Choices below, but can only select one of the option.
Box 2: Choices
You can customize forms (main, quick create, and quick view) and email templates by adding multi-select columns that are called Choices. When you add a choices column, you can specify multiple values that will be available for users to select. When users fill out the form they can select one, multiple, or all the values displayed in a drop-down list.
Reference:
https://docs.microsoft.com/en-us/powerapps/maker/data-platform/types-of-fields