I think, each person can become a successful trader.
That is only possible if the person studies for many years and practice for many years. A certain man once said: "Practice leads to perfection"
So, i ask about platforms which is simple to use 
this is a subject that you should take very seriously, you should evaluate the following points:
- Do you know the owner of the exchange?
- Do you know where the exchange is located?
- Would you trust your documents to this exchange?
At the moment I would say that Binance and coinbase are the best options
PS: You should check if your country has support on the coinbase