***** NOT A TEACHER *****You may be interested in what I found in Webster's Dictionary of Synonyms (Springfield, Mass., U.S.A.: G. & C. Merriam Co., 1951), page 418:
" Modest is now often preferred to humble in describing a person who takes no credit to himself for what he is or for what he does;
the term usually connotes a lack of boastfulness or show of conceit, but it does not necessarily imply, as humble often does imply,
a deep conviction of one's unworthiness or inferiority."
*****
I do not know your level of English fluency. So may I try to explain those words in easier English?
Let's say that you are a super chess player. You always win a chess game. If you are modest, you do NOT say: "I am the
greatest chess player in the world. Look at me, everybody! Do you want my autograph?" If you are modest, you always
shake hands with your opponent (who lost) and congratulate him/her on playing a good game. When people congratulate you,
you just say "Thank you." BUT maybe you are NOT "humble." That is, you do NOT say: "Oh, I do not know how to play chess.
Oh, it was just luck!" You know that you DO have an exceptional (special) ability to play chess that no one else has, and you
(quietly) accept that fact that you are superior to other chess players.