tester doubt

 
I have a doubt.if I do the bactest to an EA that gives me € 1000 of profit but forward gives me € 100 as I have to wait if I put the EA in real?
 

You can try MT5 for "Every tick based on real ticks", and it will be same as you are trading EA in real with same broker.
More information - 

Testing trading strategies on real ticks and the explanation is on this post.

 
There are many factors to consider in live trading, like the slippage and re-quotes for example, in back testing you will never experience these things while in live trading your EA will experience this conditions that is why the results will definitely differ.
Reason: