...no money is too small to be invest.
Depends. If you have a small amount of money saved you will probably have a low income and those small amounts invested in the future may be significant for you. But another may be quite invested and have small savings for an emergency that he will not invest.
No one denies the potential of investing in bitcoin, but it is puzzling that many people do not care about these basics. We still need fiat in our lives and will even depend on it for a long time as long as it remains the primary currency in our economy. We should invest in bitcoin but only invest with idle money and make sure it is money we do not need in the future <...>
This is what I meant. I think the OP should learn the basics of personal finance first.