what phone do you have? your system os will also be a part of the 64gb that your phone has. it will never be the 100% of the internal storage that it is said to be advertised.

 

No, Android is never 58GB in size. Android 11 on my phone is more like 10GB, and that includes twinned system partitions, though some manufacturers allocate more space than that to the system (*cough* Samsung *cough*).

What does your system storage menu show? Can you post a screenshot? Most importantly, what type of phone is this supposed to be? And I say "supposed to be" because not knowing what it is or where you got it from I have to consider the possibility that you bought a (probably Chinese) fake from somewhere, which may actually have a lot less storage than the phone it pretends to be has (and would often be programmed to lie about this until you run out of space).