The least you can do for your pup is to feed him well. We've forced dogs to be our pets and they depend on us for most of their needs, so give your dog some good quality food since he can't choose for himself!
Here are some tips on finding the best dog food below.
Ideally, a raw diet would be best since it offers high-quality protein, the right amount of calories, variety, and many other benefits. But it's not always doable for financial and other reasons. Finding a good-quality kibble works, too.
Learn about ingredients
First, let's talk about why you shouldn't buy any dog food that is sold at a grocery store. These brands are the cheapest, lowest-quality food you can possibly find. Foods like Beneful, Kibbles 'N Bits, Pedigree, and Ol' Roy are terrible for your dog - they are full of fillers which are useless ingredients like rice bran or corn bran. These fillers provide zero nutritional value to your dog and add pointless calories. Their are also harmful ingredients used in these types of brands like corn syrup, food dyes, and artificial preservatives. The first ingredients in dog food should be actual meat, not meat by-products (which are the eyes, beaks, feet, etc of the animal), or starch.
Know your dog's needs
Always feed according to your dog's stage in life - only feed a puppy a food that is specifically made for puppies. Dogs over 7 years of age should be eating kibble formulated for seniors, and so on. Puppies, adults, giant breeds, and senior dogs have fairly different needs and require more or less protein and calories depending on their age and breed. The development and health of your dog can be negatively affected if you don't provide the correct nutritional values they should be getting.
Know what to look for
Research different dog foods using dogfoodadvisor.com (they are reputable and you can sign up for email alerts on recalls), and consider the quality of what you are feeding now. Try to give a food that is at least 3.5, or preferably, 4 - 4.5 stars on their rating system. In my opinion, 5 star dog foods are extremely pricey and at that price point you might as well feed raw, if you prefer.
Compare foods and pick the best one
Look through local pet stores or online stores like Chewy.com or Amazon to find several dog foods within your price range. Then compare them on Dog Food Advisor and pick the highest-quality food you can afford. Pay attention to each formula's rating within a brand - the same type of food might be higher quality if it is the chicken formula vs. the lamb formula, for example.
Introduce your new food slowly
Once you choose a new food don't forget to slowly transition your pup to it. If you carelessly switch their diet cold-turkey you can cause some serious gastrointestinal issues, and those are not fun to deal with as a dog parent!
If you want to do some more research, feel free to read this insightful article on the best dog foods by Reviews.com here.