naif

nouns

a naive or inexperienced person
naif
is a type of (narrower)
a person who lacks knowledge of evil
inexperienced person, innocent

adjectives

marked by or showing unaffected simplicity and lack of guile or worldly experience
"a teenager's naive ignorance of life"; "the naive assumption that things can only get better"; "this naive simple creature with wide friendly eyes so eager to believe appearances"
naif, naive