Is enlarging parts of the body and plucking eyebrows considered polytheism (shirk) for changing Allah's creation, and is listening to songs that contain polytheistic or blasphemous lyrics, such as "You are everything in my life," considered polytheism (shirk), even if it is merely listening without repetition?

Sins vary in their gravity, and shirk (associating partners with Allah) is the greatest of them. However, not every sin constitutes major shirk that expels one from the fold of Islam. Plucking eyebrows (namṣ) and altering the body for beautification purposes are forbidden and are considered major sins. They are not considered major shirk, but some scholars refer to them as "minor shirk" or "hidden shirk" because they involve prioritizing one's desires over divine law.

Modern songs accompanied by musical instruments are forbidden due to their negative impact. If their lyrics contain polytheistic phrases, then whoever utters or sings them, knowing their meaning, becomes a disbeliever. The listener who is aware of their content and content with it is a partner in sin. As for the phrase mentioned in the question ("You are in my blood and you are the most important"), it is not shirk; rather, it is an exaggeration of love. Listening to it is prohibited because it incites desires and is accompanied by forbidden musical instruments. Forbidden singing is either that its subject matter is corrupt or it is accompanied by a forbidden musical instrument.