How to allow access to only one directory via htaccess?

Question

Apache HTTP Server

There is a directory with 4 files and 4 folders. It is necessary to prohibit access to all these files and folders except for one, it is called "folder". How can I do that?
This is how I get a 500 error:

Require all denied
<Directory "build">
  Require all granted
</Directory>

So everything is closed:

Require all denied
<Files "build">
  Require all granted
</Files>

Answer 1

Can be read from .htaccess documentation - access denied!
here is an example:
Order Deny,Allow
Deny from all