When you consider that the club head is very small and can be swinging towards the golf ball at upwards of 100 miles an hour, striking the golf ball can seem like a very difficult proposition, and striking the golf ball consistently is one of the big differences between good players and higher handicappers.
The sweet spot on the golf club is around about the size of a medium sized coin. Any shot that hits outside of this area will not fly as the golfer intended.
There are two main concerns with ball striking - did you get the correct vertical height, and did you get the right lateral position? A fault with the vertical plane would cause a thin or a fat golf shot and a problem with the lateral plane would cause a toe or heel striking problem.
Every area of your golf swing and setup can have an impact on the ball striking. Your primary focus in order to improve your ball striking should be attaining a correct and consistent set position, maintaining a stable spine angle during your back and through swing, and maintaining balance throughout your swing from setup to finish.
Many golfers struggle with inconsistent ball striking without appreciating that they have an issue. I recommend using face tape or any tape that would allow the ball to leave a mark on the face at the point of impact. Assessing the impact mark and the consistency of the impact mark will give you the first understanding in order to help you improve your ball striking.