The 19-year-old was charged with assault and is to appear at a committal hearing in Albany later this month.
Williams will spend time with other volunteers from the charity, starting on Wednesday evening, assisting in the soup vans set up for the underprivileged across Melbourne.
Collingwood coach Nathan Buckley said the club felt it was necessary step in Williams' development.
"We feel it's a good opportunity for Marley to see a different side of things," Buckley said at the Lexus Centre on Wednesday afternoon.
"We believe it was important for us to act appropriately and accordingly and promptly, rather than sit around and wait for someone else's judgment."
In a statement earlier on Wednesday, Collingwood director of football Geoff Walsh said Williams had the club's full support.
"While we remain very supportive of Marley, the fact is he was out late, drinking, and put himself in a high risk scenario," Walsh said.
"We believe Marley has already learnt from the incident and now recognises that he had the opportunity to make a better decision.
"He is certainly remorseful. Hopefully, the next 10 weeks will impress upon him the need to uphold the values and standards of the Collingwood Football Club."
Williams joined the Magpies as a rookie in 2012.
After playing six AFL matches last season, he was promoted to the club's senior list for 2013.
