I think you should start from basics.
Beginner stuff like - 'HTML(5)',
Designing with 'CSS',
making it responsive with 'Bootstrap', 'Javascript' for client side validations,
'SQL (MySQL or Oracle)' for database purposes and usages,
and a language for server side processing, like - PHP, ASP, JAVA, Python or any other language of your choice.
that's what I call a web developer beginner pack...
Good Luck...
