>>895273The LEDs in the keyboards in OP's pic are probably ones that allow digital color selection. The general term for these is "ws2812 LEDs".
These are controlled by I2C (a type of digital serial control, that allows individually controlling a lot of different leds with only 1 digital control line).
These are the ones that Adafruit sells as their "NeoPixels", but lots of other places sell them too.
Note that WS2812 LEDs are "surface mount components"... If you know nothing about electronics and have no access to good soldering equipment, then you want some that are already mounted on PCB's. Adafruit sells ones like this as their "Flora RGB Smart NeoPixels" but they're kinda expensive. Lots of other places sell the same kind of thing--where each LED is mounted on its own little PCB already, so it is easier to work with.
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If you just want LEDs that will automatically change colors on their own, you can get that too.
There are LEDs around that have different behavior hard-wired into them, so they do their thing whenever you apply power--but then, you cannot change what they do.
This place sells some RGB leds that slowly fade from one color to the next: search google for "lighthouse leds 5mm Round Top RGB Slow Auto Change LED"
Electronic Gold Mine has some at the moment that flicker different colors, then slow-change the colors, and then repeats again. They are calling these "rainbow LEDs" if you search there.
If you want this type of LED (that automatically changes or flickers/fades/flashes) then you *really* need to search around online, because there isn't any standard names that I'm aware of--and you can find auto-change LEDs that do all kinds of stuff, in all kinds of colors.
