Learning web development languages are simply a matter of understanding, practice, and proper implementation through experiments. So, describing a definite tenure for learning such skills is impossible.
The learning time of the languages varies from person to person depending on their dedication to learn it. Their ability to capture it, with the amount of practice and lastly proper implementation of the logics.
While it can take even more time with no prior coding or programming knowledge.
While Someone who has just begun with coding would definitely take a longer time.
HTML takes a week to have a grip over. And the maximum is an extension of two weeks you can have good knowledge on how to work with HTML.
Check out, How long does it take to learn HTML? to know the matter in detail.
CSS assures preliminary designing of your web page or website. Even CSS is easy to be learned. You can learn CSS in 3-4 days with some prior coding and programming knowledge.
Check out How long does it take to learn CSS? to know it in detail.
However, these are all approximated values of time take to learn these skills.
If you are working on these skills simultaneously, consider at least half a year to grasp over the three, with keen dedication and sheer determination.
But if you learn the three, it’s worth it. And with the knowledge of three, you are good to go and work as a Front-end developer.
But other than python every programming languages have nothing to do with each other.
It is a high level interpreted language and can easily be embedded with other languages like HTML, Java, etc.
You can join as a Front end developer in any company. Keep up at learning other languages too as knowing the other domains of web development would uplift your job position and would help you secure a better place as a web developer.
The approximated earning structure is based on the USA and recent times. The value may change with countries and over time.
The other very prominent choice can be learning from W3Schools or available online blogs.
You can refer to the vividly available E-books from the Internet.
Or you can even choose to go for paid courses from Udemy.
Know how to create a free website and earn money.
Related read, How to code a website?
HTML is the basic strata of web development. It features the skeleton structure of any web page or website. So, to get the best of your skill and be successful as a web developer, choose to learn HTML first.