The use of "one" is an old style of language, when now used, gives an air of over formality.
**Try**
"Even if a person studies to an old age, they will never learn everything."
or
"You will never stop learning." "There is always something to learn."
-->In English language (American), always try to say more with less.<--
**Revised**
"One can never stop learning."
[Common American phrase used formally as a philosophical conjecture].