If you're just starting learning a web development and looking for some high-quality free resources, this is exactly for you. I have tips for everyone, whether you like just videos, interactive tutorials or books. Let's get into it.
freeCodeCamp
This is a huge one. You choose the path according to your specialization. Then you just have to follow it, everything is laid down for you. It will be a long journey and would require a quite amount of dedication. However if you finish it, you will have some pretty solid foundations which should be enough for a junior position.
Codecademy
Well-known tech educational provider. They have interactive learning courses, so you participate right from the start. There are also paid courses, but the basics are free. It's one of the resources I used when starting with web development back in the days.
Scrimba
This is also the interactive course provider. You can expect similar experience to Codecademy. They are relatively new with a lot of high-quality free courses. Their most comprehensive course called The Frontend Developer Career Path is paid but I think it's still a great deal.
Harvard's CS50: Introduction to Computer Science
An amazing free course directly from Harvard itself. If you're into uni type of learning, this is exactly for you. There is a lot of theory you don't find in any other resource I introduced here. It's more general, not only about web development. I recommend it to build initial knowledge about programming, so you find out what it's all about.
https://online-learning.harvard.edu/course/cs50-introduction-computer-science
javascript.info
Great, thorough explanation of JavaScript and web concepts. At the end of each lesson are exercises. I visit this site when I need to refresh something, especially the things I don't use every day. Really good up-to-date info, beginners friendly.
Eloquent JavaScript
The last tip is a (online) book. Its subtitle says - A Modern Introduction to Programming, and I have to agree. Good explanations, complemented with demonstrative illustrations and interactive exercises in the end of each chapter. It's not just another boring book having hundrends of pages! You can digest this one pretty easily.
There are a lot of learning resources on the Internet, especially for the beginners. Some good, some pure garbage. The ones I mentioned here are my favorite I can guarantee quality for.