Brief Answer:
Eat high calories food

Detailed Answer:
Hello dear welcome to Ask a doctor's service.
I read your query and here is my advice.
I think you may need to choose better the type of food you eat. You may prefer carbohydrates as the base of your meals using pasta, rice , bread, potatoes or other starchy carbohydrates.
You can also add protein in your plate such eggs, red meat, fish , beans etc
Also choose plain yoghurt, milk and cheese.
You can also eat plenty of fruit and vegetables especially bananas, grapes , figs etc.
Eat at least five times per day.
Hope I have answered the question.
Let me know if I can assist you further.

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