Include files can be used anywhere in your configuration file, to help it be more readable and to enable you to re-use parts of your configuration. To use them, make sure that the files themselves contain the syntactically correct NGINX configuration directives and blocks; then specify a path to those files:
A wildcard may appear in the path to match multiple files:
If the full path is not given, NGINX will search relative to its main configuration file.
A configuration file can be easily tested by calling NGINX as follows:
nginx -t -c <path-to-nginx.conf>
This will test the configuration including all the files separated out into include files, ...