It is a myth that dogs won't listen if they're allowed on the furniture. The only reasons to not allow dogs on furniture are, you don't want them there or they won't move when asked to.The "off" cue means all paws on the floor and off the furniture or person.
It's ok if you want to use the cue "Down" instead of "Off", but a different cue will be needed for asking your dog to lie down.
If your dog jumps on you, use 'Off" instead of no, and completey ignore them until all paws are on the ground. ANY attention will reward the jumping, even if it's saying "No" or pushing them away. Leave the room for a minute, if necessary.