Of course you need to invest your fiat money for any business and there's no business that you can invest freely? Depending on what do you think that will make you productive, whether it's with crpyto currency, trading or buying and holding bitcoins, go for it. But if you think you are going to be more productive with real business like properties, its good too.
Real world investments are always better then online investments as when you invest in real world you are into one to one agreement and chances of getting scammed are lower which is totally missing in bitcoin investments as majority of investment sites turns out to be scam in long run.