Do you think eating only bread and omelette daily is a balanced diet?

No. Life will become painful in a few weeks if you don't eat vegetables. Two slices of whole grain bread daily, or veggies with every meal, are required to keep the colon clean. Study some books about nutrition so you know how to eat right.

Eggs are fairly nutritious, and contain all the essential amino acids. Fat is also vital as we cannot live without some fatty acids which the body can't make itself. Vary the fat used. Use olive oil, butter and coconut oil for medium chain triglycerides, and omega 3 enriched fish oil. You can also use palm oil. The bread will provide carbohydrates and dietary fibre as well as vitamin b (and e if seeded bread). Adding meat and vegetables like onions, garlic spinach and tomatoes will make the omelett more healthy. Drinking milk or adding cheese will provide vitamin D. You could survive off this if it were a healthy omlette, but your diet could be improved upon my expanding your range of foods.