What is 'tout-de-suite'? It sounds like some kind of French.
It is French and means 'immediately'. It is used occasionally in English.
What is 'bring it down a notch'? I think this is sort of an idiom.
A notch is used in the sense of a 'level' or noticeable amount.
Tail = a girl, in a sexual manner.
It's not clear to me what the father means. I suppose he's trying to console the son. The expression means that you might not be the person who got the result, but you could gain some benefit from it.