Speeding Up Your Piano Playing.
The speed at which you can move across the piano keys depends on three crucial factors.

First, it's essential to leave on time. Second, taking the shortest route possible can greatly enhance your efficiency. And finally, the speed of your movements itself plays a significant role.

1-As famously quoted by Dutch football player Johan Cruijff, "If you leave earlier, you appear faster." This principle holds true when it comes to piano playing as well. Initiating your movements at the right moment creates the illusion of increased speed. When you leave earlier you arrive earlier.
Utilizing the pedal can assist in sustaining tones while you navigate the keys. However, for many pianists, releasing the keys poses more difficulty than pressing them. Overcoming the fear of letting go is crucial to avoid arriving late.
2- To optimize your speed, it's important to minimize unnecessary motion through grotesque movements. Making direct and purposeful movements towards your target and patiently waiting for the right moment to strike will greatly improve your effectiveness.
3-Inadequate technique or slow movements can quickly lead to a decrease in speed. Establishing good fingering techniques and, perhaps even more importantly, maintaining a relaxed posture and fluid movements will facilitate seamless transitions to higher gears without stiffness or rigidity.

In summary, remember to leave on time, aim directly for your goal, and maintain a relaxed approach. By following these principles, you can enhance your speed and overall performance on the piano especially chords and octaves..

And don’t forget the help of the sustain pedal.