Basically, could I say something like, QFT is about fields, but what are the fields, are they in something, are they self instantiated, what makes the fields?

Basically, could I say something like, QFT is about fields, but what are the fields, are they in something, are they self instantiated, what makes the fields? We can describe the fields, but we can't get behind them, the how and why? At least we can't get behind them yet, but if we do, do we know the how of that or is it just another layer?