Reddit reviews Think Twice: Harnessing the Power of Counterintuition

First of all, ignore the downvotes. Everyone has to start somewhere, and 17 is about as good as it gets.

I agree with u/brandonIsAFreeElf that the best investment you can make at your age is personal development. Video game addiction is a real thing, and if it's affecting your mental health, take care of yourself first. Investing is great life skill, but money won't solve every problem. I also agree with his point about focusing on future earning potential. The more money you have to invest, the more money you can make investing.

Unfortunately, the other users are correct that $500 is too little to get started (see edit below). That will be chewed up with trading fees and charges for being under minimum account balances. I think the recommendation for parking it in a high interest savings account is a solid one. If you aren't working, try to land a part time job to build that capital up (to maybe $5-10K?). This is old man stuff, but you'll appreciate the effort that went into it and you'll be more afraid of losing it. Risk management is a critical skill in investing. While building up that capital, learn as much as you can. Maybe open a paper trading account just to practice implementing some of your ideas.

I can offer some broader insights that I wish a mentor had told me when I was starting:

• Learn investor psychology and always stay objective. There are two things an investment can do for you. It can make you money, or it can lose you money. Consider the upside and downside every step of the way. Recognize tunnel vision, recency bias, confirmation bias, etc. These skills will teach you when to take profits instead of being the fool who doubles down. The best books I've read on this subject are Thinking Fast and Slow and Think Twice.
  
• Learn how the broad economy works (at least the basics). It's great to learn all the ins and outs of a particular company. But if you don't understand, for example, how a slowdown in the US, Chinese and European economies affects oil consumption, you're going to have a tough time trading oil stocks.
  
• Learn market history. If you zoom way out on market charts, you'll see something interesting. Markets work in cycles. They go up for a while. They go down for a while. There are different strategies for dealing with this. Just recognize it's happened all through history, and will continue into the future. I can't recommend this video from Ray Dalio enough. Watch that a few times over the next few months. Then download and read his Navigating Big Debt Crises book.
  
• Learn the asset classes. Investing isn't all about stocks. You can also make a lot of money in real estate, currencies, bonds, commodities, precious metals, etc. Having a decent understanding of macroeconomic cycles and market history can point you towards which assets are bound to outperform under different conditions.
  
• Consider your sources. It's great you're looking for advice, but realize 95+% of us are amateurs. If you put some effort into learning, you'll start recognizing all of the classic investment mistakes in recommendations here. Watch Ray Dalio and Stan Druckenmiller interviews. Watch Real Vision interviews. There are plenty for free on Youtube.
  
• Just keep learning. Economies and markets are dynamic. The best investment strategies of the last 30 years likely won't be the best for the next 30. You have to evolve.
  
  Hope that helps! Feel free to PM me if you have any questions, or I can answer them here.
  
  Edit: I noticed another post here recommending a Wealthsimple Trade account. I was unaware of this option, so I take back my comments about $500 not being enough to invest! However, I do still recommend taking a step back and learning some fundamentals before throwing your money into the markets.