Shes still a pup - lilly used to do it as a signal that she wants something -usually for a young bulldog its hard to get on the sofa on their own -besides its also an accident waiting to happen if she might slip and fall while trying to jump up -shes just signalling you that she wants to go on the sofa
With regards to bully being on the sofa or not-this is entirely your decision -but whatever you decide -stick to it , your baby will soon learn that "no" means" no "
We never made any ramps we just picked our girls on the sofa when we were home x
Growling -in pups its usually frustration / or in play natural reaction ;-)
Separation anxiety -how do you do it ? Do you just go out or lock her and she can still see or hear you? We used to leave home starting from short periods of time and slowly increasing -we also at the begging left a filled kong to keep my girls out of trouble and associate "alone time" with a good thing crying/barking will soon stop