If your dog shows guarding behaviours, leave them well alone when they are enjoying food or playing with toys by themselves. If you need to take something from your dog, swap it for something else that your dog considers to be equally or even more valuable. Offer your dog the better item before trying to take what they have away. You could drop several treats on the ground near your dog, so they have to leave the item to go and eat them. Then you can calmly pick up the item while they’re enjoying themselves. Always swap the dog's item for something else, being consistent and always swapping items will help dogs learn to share without being worried. You can teach your dog to drop and swap during fun training sessions, when your dog is playing with a toy, get something they like even better, offer this to your dog a little distance away from what they already have. Once your dog has the hang of this, you can add a cue word ‘drop’, over time, your dog should associate the word ‘drop’ with letting go of their toy, and you can ask them to ‘drop’ what they have in exchange for a tasty treat.