I have searched this thing way too many times on google to not write a self-post on this for the future.
Often there is a need to pull only a single file on the server since rest of the changes are not ready to put on the server or production yet.
Here is how to pull a single file from git remote
git fetch // git fetch will download all the recent changes, but it will not put it in your current checked out code (working area).
git checkout origin/master -- path/to/file // git checkout / -- path/to/file will checkout the particular file from the downloaded changes (origin/master).