And investing in bitcoin or any other crypto's are very simple. You just need to buy a single coin and there you are let it sleep in your wallet and wait for a couple of days to let it grow. And after buying and seeing for yourself to see the price move higher that's the right time to sell. Just do it again and again and you'll make money from it.
If you think that crypto's is not successful yet. It's better to see for it again because many of the people here are successful with their investments in crypto or maybe it's just you that thinks crypto is not entirely successful. I don't know how you are looking with it and you are here in a crypto / bitcoin forum and saying such thing like that.
Especially when you consider how volatile everything is most of the time, it can be considerably difficult to actually be comfortable with keeping money in crypto of any kind.