So, "blonds" refers to multiple blonde people.
Here are some examples of how you can use it:
* "Il y a beaucoup de blonds dans cette école." (There are many blonde people in this school.)
* "Les blonds ont les cheveux clairs." (Blondes have light hair.)
* "Les blonds et les brunes sont tous beaux." (Blondes and brunettes are all beautiful.)