From the answers to this question
I understood there are multiple platforms to trade Bitcoin (Coinbase and Kraken were mentioned). Suppose I want to invest a small amount in Bitcoin and sell it in three years, i.e., I want to make a gamble: it's more or less the same as buying a few lottery tickets. How do I do that? I guess I have to choose one of these platforms, and create an account or similar. What characteristics should I look at, when choosing among the various platforms? In case it's better not to use these platforms at all, what should I do instead?