What does 1 Corinthians 13 mean?

It is not reliable to let people tell you what the bible says. Many people will make up stuff because they don't know what it says, and many will make up stuff because they wish it would not say what it says. You just have to read it for yourself. Read a chapter of Proverbs every day. Proverbs has 31 chapters so you can keep your place by just looking at a calendar. There is no religion or nothing in Proverbs and you don't have to believe anything. Just read to find wisdom. When you are comfortable with that, then read the bible from Romans to 2 Thessalonians over and over until you start to remember what it says. That is the part that applies to Christians. Here is a book to help you to understand the bible. It's a free download and you can get a hard copy at any bible book store.
www.philologos.org/__eb-htetb/ "How To Enjoy The Bible"

Short answer: 1 Cor 12, 13, &14 contain instructions on how to conduct a Christian church meeting. Not one denomination follows those instructions. Random preachers have spread so much misunderstanding that it takes a while to unlearn what you have been told it says so you can learn what it says. Chapter 13 expresses the importance of charity, Greek word for godly love. Jesus explains charity in Luke 10:25ff - Love is when you are aware of a need and you take care of it.

It’s really telling us the different facets of love. If you zoom in to verse 4 it’s telling us what love entails. Without love one cannot be patient and kind. Love does not act indecently, brag, puffed up, jealous, is not selfish. A person whose identifying mark is love does not keep an account of others mistakes. Does not feel joy over unrighteousness but rejoices with the truth. Love makes it easy to endure all things. Genuine love never fails.
Imagine practicing all these avenues of love, this world will indeed be a better place.
Two of the greatest and most powerful commands that Jesus encourages us to follow is at Matthew 22:37,38.
“You must love Jehovah your God with your whole heart and with your whole soul and with your whole mind.” You must love your neighbor as yourself.
With these two greatest commands love is the key factor in living a happy life. Could you imagine if all of us live our lives by those two greatest commands? Love will be our dominating factor and without a doubt we will have a happy life looking forward to each day with a smile in our hearts and a smile on our face.