I am deeply confused by much of BDSM, but I am aware that some people report enjoying the experience of not having any control, of their ability to choose being taken away from them.
Can you also give an example of what you mean by "free will" such that your chosen definition does help?
OK, I can see how your definitions of those two things are tautologically identical. But this still goes with my point that both terms have many different definitions, so you can end up with situations like yours where the terms are equivalent.
Personally, I've never heard that definition of free will, to know that you are choosing; and for occasions where I don't even realise I'm making a choice (e.g. when failing to notice I've been given a false dichotomy, or which fork of a road I take on long walks), I still have what I would call a conscious experience of them… but then, for me, "consciousness" is usually "qualia" (but if the sentence is more complex then it may also be for example one of "not asleep/comatose" or "not subconscious/pre-conscious").
Likewise, my default (in the absence of further context, e.g. being on this website) assumption when I hear "free will" is that the person using those words means something like a supernatural soul, but the underlying physical phenomena which is actually backing this is some combination of hidden information and being too complex to predict, which is why we also witness animism in various forms
On the subject of not having a mental representation of what this means, I have also been pondering recently about "literally unthinkable thoughts", which may directly sound like the same kind of paradox, but is at the meta-level and about the same kind of (apparent) paradox (that isn't a paradox at all for the people using the terms in those ways): https://benwheatley.github.io/blog/2024/04/30-13.54.02.html
Yes but only one that applies here.
From oxfords: "Internal knowledge or conviction; the state or fact of being mentally conscious or aware of something."
I disagree, I think they're both very clearly defined. Both in the clinical and law sense.