According to Schopenhauer, the will is the 'inner essence' of the entire world, i.e. the Kantian thing-in-itself (Ding an sich), and exists independently of the forms of the principle of sufficient reason that govern the world as representation.

Did Schopenhauer believe free will?

Schopenhauer means that our motives are determined but we are (in some sense) free to act on our motives. In Schopenhauer's sense, free will is essentially autonomy, the ability to act according to internal drives without external constraint.

What does will mean in ethics?

Will, generally, is the faculty of the mind that selects, at the moment of decision, a desire among the various desires present; it does not refer to any particular desire, but rather to the mechanism responsible for choosing from among one's desires.