How do I change the rgb on my keyboard?

So I have had my keyboard for over a year and have never known the rgb could even be changed

I was spamming my keyboard as a joke then somehow I changed the rgb

Idk what I did my keyboard is just a cheap Amazon keyboard

It's really cheap it's from like bto or smth

So how did I change the rgb

My keyboard does have a gear key but it just turns off the rgb