yo , i saw a flame particle at 10k , but i don't exactly know what it is , is it a flame with color ? or another thing ?

Normally, when you get a flame, it's made up of tiny dots. The item lets you change those dots into whatever. You need the flame first, though.

Flame particle adds transparency to your flame.

In other words, you can make your flames have different shapes.

You need an actual flame for this to work.