Animation for homepage

I'm looking to recreate the animation of the letter D on the landing page of this reference site https://www.dsrvlabs.com/ though mine would be the letters MY instead of D.

I want the exact way they have the letter D i.e. tiny white dots of different sizes, all slightly moving constantly, with some moving away slowly across the screen and that they move when you scroll the mouse over.

Please respond with any similar experience, how long it would take and your fixed price. Thank you.