If you are serious about improving and anxious to learn as much of pool as possibly, the perfect teaching by example is immediately available to you at local tournaments.
This is where you will find good and bad examples of stances, strokes, rhythms, tactics, strategies, and etiquette. All of this right out in front of you on every table.
If you see someone using a similar stance style to yours, their example can provide an incentive to improve your own routine. The same comparison works for any of the physical fundamentals.
Any of their shooting activities can also be compared to your own. If they are more accurate than you would be with certain types of shots, study them in greater detail. Attempt to figure out what works for them and then imitate the actions on the practice table.
This is significantly better educational process than watching professionals play. Their skills are far above you and their bad habits rare. With observations of local players, you get the benefit of watching examples of the good, the bad, and the ugly.
And, it’s all free.