The code you posted is not getting the terms from the ACF field but with standard WP functions. You can do it that way.
If you’re using a radio field then it’s returning a single field and if it’s set to return the ID then….
$taxonomy = 'your-taxonomy'; // change this to your taxonomy
$term_id = get_field('tecnica');
$term = get_term_by('id', $term_id, $taxonomy);
echo $term->name;
It would be easier to return the term object, then you can just do
$term = get_term('tecnica');
echo $term->name;