verb/a.vwaʁ le kaʁ.t‿ɑ̃ mɛ̃/
to hold the cards, to hold all the aces (to be in a strong position, possessing significant advantages over someone else); to have everything one needs to do something, to deal with a situation, a problem
“avoir toutes les cartes en main pour prendre une décision” — to have all that is necessary to make a decision
Literally, “to have the cards in the hand”.