String theory vs Quantum field theory

[OCD]

TL;DR Summary

what does it mean for QFT if string theory turns out to be correct?

So QFT treats particles as excitations of their underlying quantum field, meaning that fields are more fundamental than particles. Then String theory comes in and says that actually strings are the fundamental building block of the universe and that the different particles are vibrating strings. Do the 2 theories really contradict each other or am I misunderstanding something, like what happens to the quantum field of QFT in string theory, are they completely gone or do they have a place in the theory?

 

[Demystifier]

According to string theory, QFT is still valid as an effective approximate theory.