how to trade the good and right so that we do not lose?
Can anyone advise to me on a trusted site?
For seniors please guidance ...

For me i trade only on binance and poloniex because they are trusted and secured exchanges and your investments are safe unlike other centralized exchanges.And you can't trade without looses but can try to avoid it as no one is perfect in trading.Learn some basic rules of trading and gain knowledge and experience about this crypto market which will help you to gain profits in future.