I have been thinking about getting into web development. So far, i have been able to absord lots and lots of information about HTML, CSS and Java... But there is someone I know. He says that there are web developer secrets that I'll never be able to use and those can only be learned by taking a paid course. Is this true? I mean can I not learn a thing such as this all by myself?

Guys, I need real web developers to help me out because, the ones I know are not of much help.

@aaron. It's blatently false you have to take their course. There's w3schools and other such free courses online so how much you learn is up to you.

It is said that, "Where there is a will there is a way". @aaron you have to have a strong will to learn and look for resources in the web. There are plenty of tutorials for beginners. e.g., w3schools, tutorialspoint

I set up my own webdev business - full stack LAMP development. Never took a paid course. You build things up incrementally over years, learning the limitations and foibles of each technology and language, while trying to keep abreast of new developments and ensuring backwards-compatibilty.
CSS and HTML are pretty static markup "languages", so they can be learned quite quickly. Yes there are little techniques and best practice regarding them, but the basics are straightforward. Advanced CSS can be understood reasonably early on, but not written. Many webdevs will use themes or front-end frameworks, so stop them having to re-invent the wheel all the time. You do not have to be a guru in every single thing - just competent and thorough.
JS is a reasonably simple programming language and has many similarities to other languages. You could, potentially make do without any JS at all, but not many sites produced these days do. Modern Ajax technology is reliant on JS and any trivial updating on a page that does not warrant a full form submission will rely on JS. You can pick up "vanilla" JS quite easily too. Be careful of some frameworks or libraries such as jQuery, Angular, React etc, as they simplify the underlying JS. You may find that helpful, but one day you may need to use "vanilla" JS or a different framework. I suggest you learn the spanner before using a ratchet.
Unless you just want a static site with next to no functionality, you will need a back-end technology. Quite a few to choose from.
pHp, asp.net (few), Java, Python, nodejs, Ruby (on Rails) ...
You don't have to limit yourself to one, but it does make sense when you're starting off. Look at some stats regarding employment. Do you want to use a framework, e.g. Wordpress, Drupal, Joomla? Well they all use pHp. There will be others particular to other languages.
You will need to learn basic SQL for database queries. If you choose pHp, for example, you will most likely choose Maria (or MySQL), but there are many options. The type of SQL you use may be specific for the type of DB engine.
Armed with all that ability, you can start planning the next big thing. Oh - I almost forgot about security. Don't forget about security. You will need to be a security expert to stop being hacked and stop nasty people getting at your clients' data. "GDPR" is a big thing over here.
So yep, it's definitely do-able - but do realise that you may want to warn your significant other that you will be living in a cave for a couple of years :)

commented: You remind of the following "How do I get to Carnegie Hall?" Answer: "Practice, practice, practice." +15

Hey, you don't need to spend a lot of money to learn web development but it took more time to find something good. I completed some free courses on BitDegree website, and they are good enough, even though they are free.