A Dockerfile is a text file that contains a set of instructions for building a Docker image. It specifies the base image, copies files, installs dependencies, and sets up the environment for your application. Create a Dockerfile in the root directory of your application.
Build the Docker image: Once you have a Dockerfile, you use the docker build command to build the Docker image based on the instructions in the Dockerfile. Open a terminal or command prompt, navigate to the directory containing the Dockerfile, and run the build command like this:
docker build -t image_name .