It’s probably not at first obvious, but the Radio field type is just a normal select field type. That’s probably why there isn’t separate documentation for it. The only difference between the two (Radio vs. Select) being that Radio only allows one choice (and at least one thing must be chosen). They should still work the same.
This will display your choice:
<?php the_field('example'); ?>
This will display the possible choices:
<?php echo implode(', ', get_field_object('example')[choices]); ?>
If you head on over to the select documentation, the examples should get you going.
