Hi

The first thing to do MUST be to see an internist (medical doctor).

Have a physical examination and investigations (basically blood test) to rule out any cause that can be responsible - like thyroid, sugar and so on.

In young women, it may be Anorexia Nervosa - a condition that needs Psychiatric assessment and assistance.

If nothing is found - which is highly probable - then see a nutrition specialist (Dietician). Several sittings may be required to be well acquainted.

Why only 35 Kg is your goal? It must be more. There are actuarial tables to give exact values. As a rough estimate, the last two digits of you height in centimetres should be the weight in kilograms.

Weight is like bank account. The account grows when you withdraw less (Cut down unnecessary physical work) and you deposit more (eat more).

So for short term, eat AS MUCH AS POSSIBLE / AS OFTEN AS POSSIBLE. HIGH CALORIE food / Sweets and snacks in between / Fatty foods add lot of calorie - one gram of fat (oil) has 8 calories compared to Carbohydrate (rice) having only 4 calories. Sweets have lot of ghee and sugar.
Supplement with a multi-vitamin pill once a day

THIS HOWEVER IS BAD IN THE LONG TERM / ESPECIALLY WITH INCREASING AGE / THEY INCREASE CHOLESTEROL and so on. Beware. For a short time and in young age, to indulge like this may be excused...

Have you heard of 'flour laddu'? - it is commonly given in parts of South India for the children to put on weight. Finely ground channa dhal (protein) / finely powdered sugar (carbohydrate) / made into balls by adding ghee (fat). Keep the powders ready / make a few daily / eat several of them, several times in a day!

Finally - why the hurry to gain soon? I can only guess!

Don't worry. You WILL gain. A time may come, when you may be overweight and start looking for ways to reduce!

Take care
Wishing you a weighty future
God bless you
Good luck

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