My first time to update a README file and pull request

[Try2079]

Synchronized the current English version of README.md and the Chinese version of README-CN.md

Checklist:

• [x] I have read freeCodeCamp's contribution guidelines.
• [x] My pull request has a descriptive title (not a vague title like Update index.md)
• [x] My pull request targets the main branch of freeCodeCamp.

Closes #XXXXX

"[ ] My pull request targets the `main` branch of freeCodeCamp"

I'm not sure I get the meaning of this...