How To Rename wordpress-mu to “blog”

hello,

ive been having problems trying to rename the wordpress-mu folder to “blog”. I changed it in the 2 places that i found it in the config.php and renamed the folder, but im getting errors.

What else do i have to change?

Also, another thing i am getting and im not sure what it is, i am getting this message in my dashboard
“Your feed at https://xxxxxxxxx.com/wordpress-mu/ is empty”

I dont know what has to be done there or why.

Thanks for any help.