Difficult to do without writing war and peace.
Fortunately I got help from one of your other posts.
If you google golden retriever and select images, you should see a similar collection to the one I see.
The quality of the images is all over the place, and we’re all subject to our own taste too. It’s against site rules to post other photographers work so I’ll generalise.
The images I liked the best are backlit, shot at golden hour in nature and for this you might need a reflector or a small kiss of fill light. I’d use my 135 2.8 but a zoom would do a job. (You have experience of this)
The images I liked second most are action images, usually dog running towards camera. This takes a simple low vantage point, 70-200 and blast away.
The studio shots are a bit boring, and mostly white backdrop. I think this is overcomplicated for the result, requires more space than you need for a warmer backdrop and imo one more light. To lighting (assume studio flash heads and soft boxes), I believe the standard start position for dogs is a light from either side just behind the dogs head, which I think best shows the texture of the fur.
I have no idea what gear you possess, what your budget is, or your experience with lighting, so I’ll stop here, and happy to take more detailed questions.
One other point, if it’s your dog, don’t underestimate the amount of help you’ll need to handle the dog for shooting.