Doubting without even starting

I would appreciate some advice on taking the first step on this path. I know it will not be easy but I came "roughly" prepared to trade. A quick background: I am finishing my studies in economics, a lot of intense micro and macro stuff, finance and IT are in my daily routine, so I am not considering myself a complete beginner. I have been studying financial markets for more than 1 year, decided to get a deep dive into what is about investing and trading, understanding a lot behind the scenes, from order books to ETFs and their structure, and the economics of prop firms. In my repertoire are books about finances, money, start-ups, economics, and a couple about trading. I already know finance and data is my thing. **Still, I have not done a short-term trade** (I have a long-term investing portfolio, but that's a different story). So here is my doubt: is it really possible, of course depending on the risk management and strategy, to get profitable on a consistent basis and potentially switch the salary with trading profits? What is the competitive advantage of a retail trader against quantum hedge funds and market inefficiencies canceled in 1ms? I have been listening to a lot of videos but at the end, with all their "open willingness" they end up selling either a digital product or a course, so I continue to question myself if is that how they make their money, through trading or just marketing. Of course, some "experts" are talking about considering macroeconomic factors, but I consider these as mid-long-term investments. What about the 10 seconds up to some hours trade and exit? I want to hear back from someone who is really profitable and maybe get an initial advice on how to take the first step. I am the type of guy who is "procrastinating" because I want to learn everything what's behind before actually starting out. P.S. I also prepared myself a strategy based on technical analysis (support-resistances and price action), also back-tested and seems working fine, around 1:2, 1:3 R:R.