Imagine trying to learn photography by only reading your camera's manual. You're never actually going out in the field, taking a shot, adjusting the camera settings or seeing how light hits your subject.
Or learning to cook by memorising recipes. You'll never chop an onion, taste as you go and develop that feeling when the pan is hot enough.
I doubt you can learn to play the guitar without holding the instrument in your hands.
I imagine in some way you'll pick up some things. But that's not how real learning works. And that's not how you get good at it either.
Now, here's what practicing accessibility actually looks like.
As a designer, you're thinking from the start about how people with different assistive technologies (AT) will access your design. You're testing your colour choices with a contrast analyser while you design, not after. You're sketching wireframes with keyboard navigation in mind from the start.
As a developer, you're coding with accessibility tools open in your browser. You're navigating your own work using only a keyboard. You're installing screen readers and actually using them on your work as you do it. When you write a form, you're immediately testing it with AT, not hoping it works later when you release it.
And as a project owner, you're including people with disabilities in your user research from day one. You're budgeting for accessibility testing the same way you budget for security testing. You're making accessibility a part of your definition of done, not a nice-to-have feature you might add later.
You're actively building your passive skill. It's that muscle memory where accessible choices become automatic. Where you don't have to think twice about semantic HTML or proper heading structure because you've practiced it so much it's just how you work.
But you have to do the work.