@Isabella337 Did you read the terms of the cancellation policy on the place you booked? When you book a place, you are bound by the cancellation policy that was in place when you booked. You could message the host and explain the situation- some hosts are willing to refund in full, especially if the booking is far in the future if they are able to rebook the dates once you cancel. But hosts aren't obligated to do that- they have a cancellation policy for a reason. Be aware that the host doesn't get paid anything until after a guest checks in, so the host doesn't have your money right now.
But even if the host does agree to refund in full, that has nothing to do with the Airbnb service fee you were charged on the booking- you won't be eigible to get that back at all.