First off, I highly recommend reading my answer to What is the smallest change to physics to allow magic. It is the dual to your question. You ask how to limit magic to be physical, and they ask how to change physical to be magical. They're a good pair of questions.
The reality is that we can't tell you what is bound by the laws of physics, because we don't know them. We talk about "laws of physics" like "nothing can travel faster than the speed of light in a vacuum," but really that's just our own hubris. We humans wrote that law... what's to say the universe really follows it.
That being said, Sanderson's First Law of Magick is:
Sanderson’s First Law of Magics: An author’s ability to solve conflict with magic is DIRECTLY PROPORTIONAL to how well the reader understands said magic.
If you are trying to make your magic "realistic," then you are assuming that the reader's understanding of your magic will be based on the physics they know. If you try to write some magic engaging string theory, you'll probably get away with it... unless your target audience is string theorists. Then they'll criticize your lack of knowhow.
The list of checks I would make on a physics-based magic system for an average reader would be:
- Conservation of Energy -- This is a very important fundamental law that we've written. Much of what we understand in physics has underpinnings in this. In any reasonable Lagrangian system (fancy word for "the systems you typically might think of"), conservation of energy is tied via Nother's theorem to time invariance. If your system creates or destroys energy, it requires the laws of physics to change over time. Fun to write about, if you have the mathematical background for it.
- Speed of Light -- Don't go faster than it unless you're willing to write your own physics. So many things break down if you permit faster than light travel that you are almost forced to bring in the handwavium if you do.
- Conservation of momentum -- This is a funny one, but a big deal for speedsters (superheros who travel faster than humans can, like The Flash). These speedsters almost universally break this law. Like the conservation of energy, this one has a symmetry tied to it via Nother's theorem. Conservation of momentum is tied to translational invariance. If you break it, it means the rules of physics are different for different places. If you have a "center of the universe" where a ruler rules the universe from their throne, your story may support breaking conservation of momentum. Otherwise, make sure it works.
- Conservation of angular momentum -- Almost nobody thinks of this one, other than perhaps ballet dancers and ice skaters. You can probably write a story that forgets about angular momentum and get away with it. However, I like to include it on my list because its Nother's theorem symmetry is orientation invariance. If you break this law, the laws of physics are different based on which direction you are facing. This one is fascinating to me for plot purposes because there is some preferred direction almost egging the hero on towards the book's conclusion. This lends itself to breaking the rules, but it can be hard to see how.
- Don't play Quantum Mechanics mumbo-jubmo unless you actually understand the theory. It's so easy to write bad QM science fiction magic. If you know what you're doing, by all means, go for it, but it's trivial to accidentally do something atrociously forbidden in QM, like transmit classical information via entanglement. Leaves a bad taste in my mouth.
There are two powerful entwined concepts which I highly recommend for magic magic out of physics. The first is information. Knowledge is power. I may not be able to violate the conservation of momentum to stop a bullet coming my way, but if I know where it's going, I can simply choose not to be there. It's really hard to distinguish between a wizard and someone who simply knows a secret law of nature. I played with this in an answer to one of the Alynn the Scientific Mage questions a few years ago. Indeed, if you want some prior art to work from, just search this site for Alynn!
The second concept is unmesurable quantities. Science works based on measurements. If your world is affected by something that is not measurable, science simply cannot help you. One obvious example is that you can't see if a gun is going to fire if you can't see their finger. In that case, we could argue that you could see the finger, if you were in the right position. But what if something was truly impossible to measure? What if the spirit of a man going to war is actually not physical, but some unmeasurable metaphysical thing? In such a case, those unmeasurables can do curious things which are very convenient for plot.
Remember how I said not to do QM unless you really understand it? Well QM has unmeasurables. The uncertainty principle stems from the fact that it's impossible to simultaneously measure the amplitude of a wave (maximum strength) and its phase (is the wave going up or down) with perfect precision. Some aspect of that wave has to be unknowable, according to the laws of QM. Can you abuse that to make your magic? If you're comfortable with QM, sure. If not, then this is just an example of where the real life scientists start putting out theories that are borderline not "real." The actual scientific concept is called "local realism," and it's a hot topic among people who work on QM. Some of the standing theories don't support this concept of realism at all, and it bugs some people.
So that's some things that you can do, and some you can't, and some you shouldn't. Beyond that, my best recommendation is to be a "red team" of sorts. Take your physics-ish magic rules, and try to break them. Ask yourself "If I was trying to ruin this book, using these laws, could I do it?" Think like Amy from Big Bang Theory, when she demolishes Indiana Jones and the Raiders of the Lost Ark.
