Good evening, Albert.
Although they are synonyms, I believe you should read: https://forum.wordreference.com/threads/fair-vs-blond.791381/
is also an idiom.
1) an up-and-coming person;
2) someone who is treated as a favorite or considered especially promising by a superior or the members of a group.
- claro; fair hair
: cabelo ou pelos loiros / louros.
Meaning: light-colored; with light-colored hair and skin.
In British English it is usual to spell this word blonde
when writing about a woman or girl and blond
when writing about a man or boy, although the spelling blonde is sometimes used for men and boys too.
In American English the spelling blond is often preferred for either sex. Blonde may be used to describe a woman’s hair, but it is sometimes considered offensive to refer to a woman as ‘a blonde’ because hair colour should not define what a person is like.
"His hair was fair
and the skin on his face, which used to be pink, was red and rough from cheap soap, old razor blades and the cold of the winter that had just ended".
"Seus cabelos eram loiros
e a pele em seu rosto, que costumava ser rosada, era avermelhada devido ao sabonete barato, as velhas lâminas de barbear e o frio do inverno, que já terminara."
(1) Random House Kernerman Webster's College Dictionary. 2010.
(2) Oxford Learner's Dictionary.