jiajun190808 can you share your php flarum info and give us more details on what command/operation you ran before the error appeared? Did you install a community extension? Can you link to it?
You appear to not have configured the Flarum paths correctly. Even for local development, it's good practice to remove the public folder. If you want to keep Flarum in a subfolder you can follow these steps https://docs.flarum.org/install#customizing-paths
EDIT: I thought you were talking about a special extension but upon re-reading your message I think you mean the error appears at the end of the initial Flarum installation? In addition to the "customizing paths" part, make sure the .htaccess file and rewrites modules are enabled on the server.
