You can grow your tbc when you invest for some site that realy are paying in return, but be careful theres a lot of investing site now that is a scam. Also you can buy and sell btc, this is the time to buy btc while the price is still low because sooner or later it will get so much more expensive. But take care also because there are lot of scammer now. You can also gumble with your btc it is an easy way. But ofcourse there is no assurance if you can win or not. You can trade something in exchange with btc. There is a lot of way to grow your btc. Don't just keep it will not grow without running it.
Exactly once. bitcoin will surely experience a remarkable progress in the future, as if seen from different facets of all other digital currencies far worse than bitcoin. But now this is the problem for the speed of the bitcoin confirmation period is growing now that this was bad enough, and it will most likely give you a bad impact in continued until 5 years