Hi…
Can I have a detailed explanation of line 6 in the first picture, and what is the benefit of the “number” in line 1 in the second picture, what function does it do.
Article link 
Hello @albaraa_1949
this is what line 6 do
it add arc
and line 1 return a number from 0 till number
Math.random() * number return float number from 0 till number (number is not included)
and floor do this https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/floor
and have a nice day 