Use the following structure:
./
|_ nginx
| |_ default
|_ Dockerfile
|_ entrypoint.sh
Copy the contents from nginx-default
to nginx/default
Run docker build -t wordpress-nginx-mariadb-debian .
Run docker run -d -p 8887:80 --name wordpress-container-neve wordpress-nginx-mariadb-debian
You can visit https://localhost8887
and run the WP install.