To make something turn-based (like your card game) you just have to limit what actions can be done at certain times. This all depends on how you set up your conditions.
For instance, if it's player 1's turn, obviously player 2 shouldn't be able to move his cards around. So add that to your condition with a variable like:
-> M&K On Left Clicked on Family "playerTwoCards"
-> System Compare "playerTurn" Equal to "1"
+ make an error sound
There's nothing built in to Construct that automatically allows for turn-based play, you'll have to create it. Just as there's nothing that automatically allows for destroying an alien ship and adding points to your score. Those are game rules that you have to define manually.
The best thing to do is plot an outline of how your game will work on paper. What are the steps you need to take during a turn? What defines the end of a turn? What information is it necessary to keep track of? Player health? Number of cards in the deck? Number of cards on the field? Create variables for these things as you need them to keep track.
Even though Construct doesn't use a programming language, it still requires a programming mindset. Does player one click the "End Turn" button? Then set "playerTurn" to 2, and do whatever else is necessary to set up for the next turn.
Good luck.