Even with an Arduino Uno. or Arduino Nano with Neo-Pixel LEDs or I2C-IO-expanders you can have 50 or even 100 LEDs with each blinking in it its own pattern and each at a different frequency
This is done by
Using a coding-technique that is pretty simple once you have understood the basic principle.
This coding technique is called non-blocking timing.
As you are a newcomer I want to recommend you to not use this
famous notorious bad explained standard example blink without delay()
This standard example does not include an introductory explanation of the difference between delay() and non-blocking timing.
The code used makes it unnecessarily difficult to understand the principle.
Users who have already understood the basic principle are almost all blind to the difficulties that a real beginner has with it if he only has the code available without a supplementary explanation.
That's why I recommend this tutorial because it contains exactly that:
- clarify the fundamental difference between delay() and millis()
- the principle explained using an everyday example
best regards Stefan