This is the 188th most frequent Italian word.
grado
"Grado" in Italian means "degree" or "level" in English.
Here, 'in grado' is used as an idiomatic expression meaning 'capable' or 'able to'.
Sono in grado di completare questo compito.
I am capable of completing this task.
'Grado' here indicates a ranking or level achieved in a context such as education or performance.
Il suo grado nel corso è eccellente.
His/her rank in the course is excellent.
In this sentence, 'gradi' refers to units of temperature measurement, like degrees Celsius or Fahrenheit.