you need to pull the docker image from dockerhub (docker repository). The following example of pulling the Apache HTTP server image.
$ docker pull httpd
Using default tag: latest
latest: Pulling from library/httpd
f5d23c7fed46: Pull complete
b083c5fd185b: Pull complete
bf5100a89e78: Pull complete
98f47fcaa52f: Pull complete
622a9dd8cfed: Pull complete
Digest: sha256:8bd76c050761610773b484e411612a31f299dbf7273763103edbda82acd73642
Status: Downloaded newer image for httpd:latest
geekflare@geekflare:/home/geekflare$
docker pull [OPTIONS] NAME[:TAG|@DIGEST]
docker pull httpd