Look for what all images you have on your system using the following command:
docker images
Execute this command to build an image and when you build the image, a container automatically gets created.
docker build -t image-name .
You can run this image using this command:
docker run -p 80:80 -it image-name
Where -p stands for port mapping which maps the container's internal port to system's port which exposes whatever running on the container.