Do you have any professional credentials like an MBA from Harvard, a CFA degree, or family lineage as a Nigerian Prince?
From 1 documentary of ABC or NBC or ... i saw lot of USA citizens have fake diplomas or degrees. Could i get finance related job in USA with this diploma? In other words is USA still land of opportunity?
No, because reputable employers check your background. Statistically speaking, there are very few people that have these. The only people that buy those are unethical people.
Demo is pretty accurate if you're following a specific pattern or strategy (assuming your position sizing won't affect the market, ie. trying a system which requires to trade 50 lots of futures or 5000 shares of expensive stock).
Demo is never accurate for manual trading since there is no slippage, limits are often instantly filled when price is touched and maybe most important of all psychology is completely different (fomo, taking profits early, moving stops, ...). If the system is 100% automated an slippage is included in the calculations then the results can be accurate, for manual trading it is not reliable.