Trading without your trading strategy is just like going to the farm to work without farm tools and I wonder if you can achieve anything at the of the day. After you think you must understand things about trading, the next thing is developing a strategy around what you learned, You should have backtesting of your strategy with a Demo account to ascertain or examine how profitable you would become with it before implementing it in a live account.
I realize that new traders are always in a rush to make a quick profit; they always have so much FOMO that they don't even see practicing on the demo account as something that is worth spending time on. They will just dive in straight with their capital, and with a few mistakes, all their assets will get liquidated, and they will end up casting blame on crypto. This is the reason why some people have negative perceptions about crypto. Just as you said, a trading strategy is what one can build when learning how to trade. Then you develop a strategy that best works for you, or even if you get a strategy from another trader, the person is supposed to do some practice on the strategy by using the demo account just as you stated, but most people just forget all those principles just to make a quick profit.
By doing practice, you'll be able to familiarize yourself in what are the possibilities and what can you do to avoid making mistake,
you'll be able to learn things and you'll be able to be ready when you step your foot inside trading.
I go with the idea of watching and following some experienced traders. They can give you good hint in performing your trade, might not
have the same outcome, but you'll be able to learn from how they execute their trades.
It's important to take time and not to think that it's an easy journey or a quick way to earn money.