Parker knows there is room for improvement with England only posing a spasmodic threat in attack.
He said: "I'm sure we will do a bit more work leading into the Sweden game on things we could do a little better.
"Hopefully we can get a little bit more going forward and go from there.
"On paper France were the favourites in the group and now we will go into the other two games and try and get a result there.
"But Sweden will be difficult. We've not got the best of records in competition against Sweden so it will be tough."