Questions of Identity

After seeing society and how words change and standards change. I notice how identities and ways of identities change as well. I noticed that most non muslims seem not wrong when they see it as a social construct or up to the culture. When I look at islams position on this wishy washyness of identity I see no islamic text on it other than urf. I am very confused as this same thing is used to act like gender is some made up thing. What's Islam's answer to identity and what exactly is the identity of one's culture, gender, status.. as ones culture can change and status or role but gender.. I am very confused. (PLEASE ISLAMIC REFERENCES, I don't want a "in my opinion" answer and sorry long question, jazakallah)