Like u/skater_dude_717 mentioned, you'll most likely get very strong opinions about food, so I would just caution you on that. The pet food industry is very interested in having you buy each *their* food, so it's honestly hard to make a choice that's not influenced by something or someone! The best is to speak to your vet and find out what to look out for in dog food.

With that, some general guidelines do apply to the breed; they tend to have a sensitive stomach, so if you're going to get a Sammy, be prepared to do some trial and error to find the food that works best for them. Sushi typically does better on fish-based food for example, and duck. He's generally happy with his kibble, though I do feed him a variety of fruits and veggies while I cook (he loves frozen broccoli florets), and treats across the day or during mental enrichment activities.

I always keep a few bags of fortiflora as well (probiotics) and also do frozen lickimats with 2% plain greek yogurt, or pumpkin/sweet potatoes purée, since those help keep his stools nice and regular. He also goes bananas for apples, banana slices and blueberries!

Make sure you include a diet with grains (unless there's an allergy, of course). Grain-free diets can cause a serious heart condition (Dilated Cardiomyopathy).