It depends. If your fixtures were originally made to accept regular incandescent lamps, ie. 1141's, then you have lots of choices, as you just need to pop one out and install another, just as you would with any bulb.
If however, your fixtures were originally made with LED's, then they were designed as a "throwaway" type of fixture and you may or may not be able to replace just the LED board or element and keep the original housing.
I highly recommend M4products.com for LEDs. They have a section for replacement boards for factory made LED lamps, and they have tons of different choices in LED "bulbs" that plug into sockets. You just need to know the type of socket and "color" of the
light. I prefer natural white, it is neither yellow, nor blue, but just pure white. M4
lights are consistent, as every
light of a specific color, no matter the bulb style, will be the same hue, with no noticeable variation.
https://m4products.com/
https://m4products.com/better-leds-f...-led-fixtures/
Charles