Gold Brokers

Is it more difficult to predict the price of gold and oil or stock prices and currencies?

Yes, it is online and not

You can buy and sell gold and oil futures. All futures contracts are bought on margin (leverage) so yes, as forex. But you must create an account with a commodity broker to handle that way.

You can also buy gold and oil traded companies related to the line if it's something to consider too.

There are times when gold and oil price movements are obvious and times when they are not. Even with currency. The best investors await an opportunity for granted and patience, because it can take years.