Use positive reinforcement techniques to teach your puppy that being calm and non-aggressive around food is rewarded.
Feed your puppy small amounts of food from your hand, showing that you're the provider of their meals.
Teach your puppy the "trade-up" game. While they're eating a low-value treat, gently offer them a higher-value treat and exchange it for the one they're eating.
Gradually expose your puppy to situations that trigger their food aggression, but at a level where they don't react aggressively.
Set clear boundaries around mealtime. Teach your puppy that they should only approach their bowl when you give them permission.