If you have a question about what to buy, then you do not have a clear plan. Therefore, you are not a professional, which increases your chance of losing significantly. An independent study of the features of cryptocurrencies is too long a journey and not everyone can afford it.
Alternatively, you can find a broker that you can entrust the investment process.
If you are planning an investment, you need to determine the amount of investment and divide it into several parts.
This will minimize your risks. Also, to study the situation about the cryptocurrency rate, I recommend that you study the information on the rating agency Crypto Rating website. Here you will find the cryptocurrency predictions https://www.crypto-rating.com/forecasts/ and will be able to assess the situation to make a decision
What do you think about the risk levels though? The recent crash proves the volatility of cryptocurrencies again.
While in short-term the Bitcoin and other cryptocurrencies are very volatile, if you take a look at the big picture you will notice that it always goes up long-term. That's why I recommend Hashing25 as your bitcoin cloud mining companion. By paying them a fee every month you will get stable Bitcoin earnings that you can sell when the price is right.