I am not an expert but i want to share my experience about lab feeding as i do have labrador.
Dont you think chapati is from wheat and wheat is a grain? my friend boxer had skin allergy after having chapati in morning, so if you are newly introducing chapati, give him littlebit and check that he should not get any allergies and then gradually increase the chapati amount.
Curd rice would be a best choice and chicken you can give either daily or weekly 3 times whichever is affordable to you. make sure that you should not give cooked chicken to your puppy as cooked chicken has sharp bones which hurts puppy throat. If you plan to give only boiled chicken then go for boneless chicken pieces.
Milk should be avoided as it may cause loose motion for puppies, instead of milk give him alternative milk products like yogurt, cottage cheese (panner), cheese, butter and curd.
Some points to remember for lab owners:
1. As labs are tend to put weight so we need to reduce the intake of carbohydrates, which includes mainly rice and other treats.
2. Next, you need to figure out weight of your puppy parents and you need to maintain the weight of your puppy accordingly. Usually puppies reach 50% of their adult weight in their 6 months of age.
3. Food and weight should be balanced, exercise is must but should not over do it as over exercise cause problems on their health later stage. Let him take good rest with nice play time.
4. You can also add egg and cod liver oil capsules in his diet, and this is for shinny coat.
5. You can also give stuffed veg rice (vegetables+rice).
6. If you want your lab to put on weight add banana and curd in his meal.
7. Dont ever try beef for labradors, try only chicken, lamb, goat, fish, turkey, duck, and egg.
8. Monitor his stool always if you see loosy and stinky stools which means something is wrong in his diet.
9. Give more exercise to his jaws by giving meaty bones/tender coconut/kong toys.
10. Avoid giving Onion, Garlic, Grapes and chocolates to labradors. these are extremely poisonous to dogs.
11. Last and finally labs are clever, he will do anything for getting treats and food, use this skill in positive way.
And this is one of my favorite line about dogs...
"Always treat dog as a dog, if you start treating him as human then he will treat you as a dog".
All the best.