Hi Mansiz,
That has to be a first for me... Replying to someone looking to get algae in their tank.
Mollies are omnivores, they eat many types of foods such as spinach and flake food. They will eat some algae tablets/wafers or leafy greens (spinach or romaine lettuce) but will also eat plain old flakes.
I would recommend algae wafers as a occasional treat but they sink because they are designed for bottom feeders (although it never stops my Tiger Barbs from nibbling on them).
I hope this helps.