Are you breathing right now, or is breathing just happening?
Both. I can stop breathing at will, or else I'll suffocate. Likewise, when I'm unconscious, like when I'm sleeping, my brain can take over the reflexive action of breathing just like it does my heart or any other vital, regulatory function in the body.
With respect to breathing, the only thing stopping me from suffocating myself at will would be the desire to live or to put a stop to what would otherwise be a painful (at first) and distressing way to die.
Are you seeing right now, or is seeing just happening?
Seeing is just happening. You can sever my reteina or my ocular nerve and I'll stop seeing, or I could simply shut my eye, but otherwise, I'm only able to see what I can point my eyes at to take in light. It happens without me thinking about it, just like hearing, tasting, or any other unconscious sensory experience.
Not to deflate the new-age fluffiness of the idea, but the senses aren't really that special. Everything from the most complex primate to the least complex insect has the capacity for simple, unconscious sensory perception like touch, sight, hearing, taste, and smell.
Are you thinking right now, or is thinking just happening?
Both. Meditation is a thing. So is the subconscious.
If you are the one thinking right now, then tell me what your next thought is going to be. It can't be done.
If I know me, my money's on "boobs."
You can control your thoughts just as readily as you control your car, but even the minute reactions at the chemical level in the combustible engine of your car are susceptible to spontaneous, random chance. So too are your own thoughts when we factor in the subconscious.
The only difference, really, is that machines tend to be better regulated, and so there tends to be less spontaneity.
Because the voice in your head that you confuse to be your own thoughts is outside of your control. The thoughts (voice) come in and out of your perception. And any action you ever take is either decided on by the voice in your head, which is outside of your control, is an impulse, which by definition is outside of your control, or a combination of the two. And in each of those cases, it is always greatly influenced by input from the outside world, which is definitely outside of your control.
By this logic, the idea of free will is shown to be an illusion. Thoughts? Do you have a different idea of what free will is? Is there a reason to think that perception of the body is different than perception of the rest of the world?
You're confusing impulse with willpower. Impulse isn't a contradiction of willpower, but rather the very thing that gives willpower any context in human agency.
If you're instead saying that everything is impulse and not willpower at all, how do we distinguish between the two in the first place? Control is the answer, and our conscious mind is the engineer pulling the levers. Impulse, by contrast, is managed chiefly by that niggling subconscious lizard brain at the top of our spinal column.
Just because we aren't in complete control of the world around us, or even our own minds, doesn't mean we have no agency in our own lives.
It's an interesting thing to think about, but it doesn't pan out, in my opinion.