Is there a way to make ladders?

I made a level where your in a house and I was wondering if I was able to make ladders because stairs take up room.

Sure. Have a ladder object either solid, for on the sides of blocks, or not solid, for on back walls. Either way, have a behavior on your player “collision with ladder” to an On/Off switch to (ON).
Have a button for Up go to (IN)
Have when the button for the button when left or right is pressed, connect to (OFF)
Have the (OUT) of the On/Off switch go to a Number 36 to a Motor (Y).

Now if you are touching the ladder and hold up, the motor makes you float up until you move left or right, and fall off the ladder.