The way it works is slightly different from a typical buy/sell exchange. Your trade by opening "buy/sell" positions instead.
Let's say you want to invest $100 worth of Ethereum.
To do so you open a "Buy" position, now the tricky part is that this position has to have "stop loss" and "take profit" values.
If let's say Ethereum goes to the moon overnight your position automatically will close when it reaches your "take profit" amount.
Of course you can set that amount really high but you can't really do that with the "stop loss" value, there is always a limit you can set it to (currently 100% of your investment).
If Ethereum goes down badly and suddenly worth less than your "stop loss" value your position will close and you lose your investment completely.
I think it's easier to just buy crypto on exchange, in that case you can always HODL and don't worry about reaching "stop loss"
Any trades please correct me if I'm wrong