The little demo you linked is far from being a proper game, or even a useful technical starting point: no score, no objectives, no rules, just imprecisely throwing a ball against a few unpleasantly floating blocks.

You could focus your effort by writing a clone of an existing game of the same genre, faithfully reproducing some example levels. You'd learn all sorts of relevant programming and design lessons and you would have a good guide on your game design and programming journey, until you are ready to introduce novel elements because you know what you are doing.

At the very least try writing down, with pictures, what an example puzzle could be like and what does it imply for the game rules and the game engine. Interesting design decisions and things to test and program will emerge spontaneously.

For example, should the physical simulation be noninteractive after an initial launch, like in e.g. Angry Birds, or should it be possible to flick the ball while it is moving, like in the current demo? Interacting with the running simulation is not an unconditionally good “feature” that you “should” add in order to generalize the puzzles, because it has significant costs and downsides:

• it rewards manual dexterity and making adjustments (at the expense of analysis and planning)
• it worsens accessibility by requiring good reflexes and realtime interaction
• it complicates the "solution space" (for example, if the ball can change direction and gain energy at any time it can reach many more places with a greater range of approach angles and velocities)
• counting attempts from a fixed starting positions or strokes within one attempt becomes somewhat meaningless
• velocities should be low, or the user interface much quicker than clicking and dragging, to allow interactions with a moving object

Taken to the maximum degree, interaction with a running physical simulation is the defining feature of realistic driving games, or (closer to puzzles) obstacle course games like Marble Madness. Is that where you want to end up? Maybe you can think of some form of limited interaction with less drifting away from the puzzle genre?

And this is only one basic aspect of one basic mechanism.