If you save your money then it's amount will remain the same.
But in case of investing it, you can increase the money, may be many folds.
Higher the risk and higher the return.
no it won't remain the same you will actually lose money if you save and nothing else, because the inflationary nature of fiat(i'm assuming that you will leave your wealth in fiat form) will be agianst the purchase power of your money, in the end you will buy less thing
this is also happen very fast in 3-5 years, because if i'm not mistaken the average inflation is around 8% per year for fiat currency