Welcome to BPO! I'm Kristine, mom to Rosie our 4 year-old Newf.
Just like the others before have said, I'd be weary about the shredded cheese supplements. You never know what will upset your dog's stomach. If plain old kibble isn't attractive enough for Molly, adding some bland boiled vegetables like peas or chopped green beans might be better (less in calories and doesn't have the additives that processed foods like cheese do). For supplements, we add some fish oil (for her coat), vitamin C (for general urinary health), and glucosamine and chondroitin (for her bones) to her food as well. Rosie's on a special urinary veterinary diet, so I can't make any recommendation s on the usual kibble.
Grooming - Get at least a shedding rake, a comb, and a fine-bristled brush. We brush at least every other day to keep those nasty mats from getting out of control. It also keeps her cleaner longer and you might get away with bathing Molly less often.
Training - We got Rosie when she was 3 and so she was trained in the basics already. But like others have said, training while she's a young pup even at 4 or 5 months would be good. Having that positive control and being able to recall them after basic training is important.
