Yes you can freeze Chicken Alfredo.
You can freeze Chicken Alfredo either whole or leftover after you've served or eaten some of it.
I sometimes will make some Chicken Alfredo the day before and then take it to a family gathering or other event and then heat it back up when I get to the place or heat it up again before I leave.
I bake Chicken Alfredo in Pyrex baking dishes which are safe for freezer storage.
I bake the Chicken Alfredo and then allow it to cool down and then place some tin foil or aluminum foil over the chicken Alfredo and then freeze it.
If you leave leftover Chicken Alfredo in the freezer it will last for up to 6 months but it's best to eat the leftover Chicken Alfredo within a few months or sooner because it loses it's freshness.