There are numerous free resources available like pdfs, articles, e-books, video tutorials, online courses and so on. But all the free resources doesn’t provide the all the required content. Go for the one that covers all the topics from a basic level and goes to advanced level. For such learning I would recommend you to watch this video by Intellipaat. This video has covered all the concepts in an organized manner from basic to advanced level. Upon watching this video one can have better knowledge about full stack web development -
Along with that if you are looking for a certification along with training then check out this Full Stack Web Development Course by Intellipaat.