Since I want to do Verify my ownership of http://www.errong.win/ via Search Console.

I tried to upload the file google9aedadfa5be8a815.html under my site's working directory where I installed via ghost instal command.
but only get 404 error while visiting http://www.errong.win/google9aedadfa5be8a815.html

Solution

Thanks to Nistor Cristian, kevin, vikas.potluri, they replied my thread quickly in ghost.slack.org and I got the issue fixed.

Nistor Cristian
simply include it in your theme and should work
kevin
@Errong add the file to the root of your theme
vikas.potluri
If you're not sure which theme to use, go to the ghost admin panel, download the current theme, drop in your google verification and upload it back to the admin interface

For my case:
I use the default casper theme, its path is :
blog/content/themes/casper/
I moved google9aedadfa5be8a815.html there and then it works.
You do not even need to restart your ghost(ghost restart).

You can use below command to check it.
curl https://www.errong.win/google9aedadfa5be8a815.html
google-site-verification: google9aedadfa5be8a815.html