What is HTML?
HyperText Markup Language or HTML is a technology that makes up the structure of a webpage. The structure of a web page is split up into different elements.
Learning this shouldn’t take you more than a couple of weeks.
What is CSS?
Cascading Style Sheets or CSS is a technology that shows how HTML elements are rendered on a webpage. This language is usually written in a separate stylesheet that is connected to an HTML document.
This will probably take you about a month depending on how much you are drawn to design.
What goals do you want to achieve?
I didn’t do a lot of back-end work myself. The hardest thing I created was a Twitter bot. A really good developer can build the entire back-end for big applications.
Developers that can do this on their own are called full-stack developers. They can write front-end and back-end code. This also takes a lot of time to master.
I have an inaccurate chart.
I made a graph that is not very scientific but it can give you an idea of the different skill levels you can reach.