What steps are needed to create a Docker image using a Dockerfile?

To create a Docker image using a Dockerfile, follow these steps:

1. Create a Dockerfile — a text file with instructions for building the image.
2. Specify the base image using the FROM instruction, for example:

   FROM php:8.0-apache
   

3. Add necessary commands to install dependencies, copy files, configure the environment, for example:

   COPY . /var/www/html/
   RUN docker-php-ext-install pdo pdo_mysql
   

4. Define the command to run the container using CMD or ENTRYPOINT.
5. Build the image with the command in the terminal:

   docker build -t my-php-app .
   

6. Run the container based on the created image:

   docker run -d -p 8080:80 my-php-app
   

Thus, the Dockerfile describes how to build the image, and the docker build command performs the build.