Research the whole market and find some coins for your investment. I prefer to invest in altcoins, because I think that BTC would be replaced in the nearest future. So pay your attention to such coins as ETH, XLM and NEO.
we all never know whether bitcoin can be replaced or not. the problem now is that the bitcoin situation is starting to improve again. so I think even though the altcoin is progressing but bitcoin is still the market leader
Well, bitcoin is unlikely to be replaced by someone due to the fact that bitcoin is the first coin that made the blockchain , I think because of this it is unlikely that someone will replace, since the market has already become a certain reliability of this coin , but in altcoins of course you need to also invest