To some extent I think it is fixed because as I know nobody made money from online gambling.
You are wrong about that. People have made money from casinos and there are proofs of that. If you keep thinking like that because you are yourself losing then you are in a delusion.
It means that online gamblings are fixed and they will never let you win the game.
Looks like you dont know what is provably fair algorithm. Most reputed casinos here have this algorithm in place and you can use it to verify the rolls to make sure they are not baised and the casino never had extra chance of winning that the player.
When you start gambling for the first time, you will win several times. It doesnt mean that you are playing well but it means that they are allowing you to win and then they take all your money.
That just luck. If you win then its your luck and its you lose then also its because of your luck. The lies spoken by people online are often because they were losers themselves or they never actually took part in it. Dont believe in those but rather try to verify your rolls to make sure they are not rigged. Some scam sites are there but the reputed well known ones are not.