Add highlight syntax

[AhnafAhamed]

Is your feature request related to a problem? Please describe.
The highlight syntax is missing

Describe the solution you'd like
Add documentation for highlight syntax

[AhnafAhamed]

@atapas I would like to work on this issue for Hacktoberfest. Thanks

[aashishxetri5]

Hi @AhnafAhamed, There's already an issue created for this #25 and a PR has also been submitted for this #26. Please find another issue to work on.

[AhnafAhamed]

Thanks for the heads up @aashishxetri5