It is bad to have that dream but the reality is such a harsh and brutal truth.
1 . BTC will be the primary money all over the world all the currency will be just secondary
It will never be the primary money of the world nor countries as bitcoin is decentralized and volatile. I think we will be seeing digital currencies of the fiat we are using in the future but I don't think it will be bitcoin.
2. All the world currency will be exchange to bitcoin slowly until its all illiminated
It is the opposite and it is happening right now except for the last part. A lot of countries do accept bitcoin and you could exchange them to any fiats that you want unless they are banned in your country. Fiat will never be eliminated.
3. Altcoins will be use for very country and bitcoin as its Superior
As I said it might be a digital form of the fiat that we are using but altcoins will stay as altcoins. It will stay as the alternative coin for bitcoin which have a higher possibility of dying before bitcoin.