Advance CSS code for background colour of Heading tags (H2, H3) in a post

It would probably be easiest to add a unique classname to that particular h2 tag and apply @Gandalf’s CSS code with that classname to target that h2 tag. For example

<h2 class="uniqueclassname">SAP S4 HANA Finance</h2>

h2.uniqueclassname { background-color: red; }

If you do not know how to do this using your Wordpress tools, we can move this post to the Wordpress category for you.