Translating the date to Chinese for a beginner

Hello!

I am very new to building websites. I have been trying to find a way to translate the date on my website to Chinese. For example it says “Dec. 12” when I list an event and I need it to say “12月12天.“ I have looked on other help forums, but frankly I just dont understand where and how to insert the codes they talk about. I am using smooth themes template called “edu”. I know how to access the documents like functions.php through the hosting site, but dont know where and what to edit in those documents. Can you please explain to me how to change the date formats in a very simple way, as if you were explaining it to a child?

Here is my website: https://www.ivylanguageacademy.com

Thanks,
Devin