Moreover actually doing a real interview can uncover where you are weak more than introspection or mock tests can.
Most companies allow re-applying later anyway, and there are plenty of others too.
One of my first interviews out of college years ago was at a FAANG company (rhymes with pamazon). I completely embarrassed myself, wasting not only the entire loop’s time but losing a ton of confidence in myself at a young age in my career. The entire experience was embarrassing.
Looking back I still have no idea how I ended up even getting invited in for an in-person loop.
My advice is to at least honestly assess any job posting’s requirements and compare to your true experience.
In my limited experience, your attention is better spent sleuthing about on LinkedIn, on the company website, and especially a dev blog if one exists. Getting to know a company is far more instructive and helps with every stage of an application.