Please explain the focus and scope of the Fourteenth Amendment.
This depends on the time in history that we are talking about.
When the 14th Amendment was ratified, it was clear that the main focus and scope of the amendment was the freed slaves. The amendment was meant to ensure that they would be seen as citizens, in contrast to the Dred Scott decision which said that they were not and could not be citizens.
Since then, the focus and scope of the amendment have changed. It has of course been used to try to promote racial equality. But it has also been used to promote the rights of women and other "minority" groups. It has been used to protect the rights of corporations. It has been used to require the states to obey the Bill of Rights, which only applied to actions of the federal government in the past.
In this way, the focus and scope of the amendment has changed greatly over time.