If you live in a metric country, which is most of the world, you are going to have to get used to feet, because that is what aviation uses (except in China and North Korea and until recently Russia). And that’s because it was mostly Americans and British pushing the boundaries of aviation in its early days. So things got locked in and now it’s impossible to change. An enormous amount of literature, manuals and equipment now works in imperial measures, and of course, pilots and air traffic controllers are so used to it that switching would cost an enormous amount of money and probably be dangerous. There was even talk and attempt of doing so back in the 1970-80s but it failed. Pretty much everyone’s given up on the idea of switching now.
Even average Americans, who work in feet, will have to get used to nautical miles and knots.
While internalizing the new measures takes some getting used to, trust me, it will come to you and will become second nature. It’s like a second language only, thankfully, much simpler.
Plus, aviation like any other field, is chock full of acronyms as well. Those will have to be learned as well, but again, that comes with getting into any new field. There is also of course the infamous Aviation Alphabet used in radio communication so that letters wouldn’t be misunderstood with different accents and noisy environments.