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[2] https://testnet.binancefuture.com/en/futures/BTCUSDT
Yeah I know about them, they are good on computer but they are not mobile phone friendly. I was looking for one of those platforms that has an app where one can set up a demo account/simulated trading
My advice to him is that he should just open a real account somewhere, and trade futures using $1 contracts. That way he is trading live and if he loses he will lose fractions of a coin instead of real money. Trading demo is not good because everyone is a great trader when there is no money involved. However if he trades pennies, there will be some fear and it'll change his outcome and it'll be harder than it looks.
2. There are no options for trading using leverage on crypto markets
He will use some money later. I wanted him to first get familiar with the different types of trades and orders as stated in the OP.