So here is my question, on the imagine below, Red one is EUR and blue one is USD, If I press sell, i sell EUR to Buy USD, If i press Buy, i sell USD to Buy EUR right ?
yes exactly
If I press sell, i sell EUR to Buy USD, If i press Buy, i sell USD to Buy EUR right ?
You are correct in this.
However when you mention:
Red one is EUR and blue one is USD
If I’m not mistaken, both prices are in the [B]counter currency[/B] (USD) as the [B]base currency[/B] (EUR) is always equivalent to 1.
So when buying you pay the price in blue of the counter currency for 1 EUR
And when selling you sell 1EUR to get the price in red of the counter currency.
Go to school > Preschool > How Do You Trade Forex? > How You Make Money in Forex
I can’t post links until I have at least five posts… 
Yup, that’s it, that’s the long and short of it - sorry, could not resist…lol