The catch is straight out in front of you, early in the stroke, not somewhere under you, late in the stroke. The catch is to the inside, close to your long-axis.
A prerequisite for a firm, definite catch is a downward aquatic line; it puts more weight on your hand.
The catch is an integral part of the stroke, but it's missing, not there, with many swimmers.
The catch is your connection to the water at the front of the stroke. It's what you rotate around.
Your hands are anchors, not paddles
Understanding the difference is crucial to improving your swim skills
You need really good balance, posture, and alignment to swim this way, otherwise you are just pushin' water.