Hi,
I am underweight and trying to gain weight. I am male, 25years, 174cm tall but weigh just 57 kgs. I look slim and my cheeks look sunken. I am following a diet of two glasses of milk stirred with egg yolk and also a handful of sprouted pulses every morning, two bananas before bed everyday. This I am doing for more than a month. Will this be a promising diet to stick to? Suggestions .

Is that all you're eating?? If that's all you're eating, no, you will not likely be gaining much weight. You may even end up in the hospital. That's no where near enough food and nutrition.

What are sprouted pulses anyway?

OOPS!!
I mean I do it along with my regular meals.

Oh. OK. What else are you eating? What sort of exercise are you doing?
And what are sprouted pulses?

Hopefully you're eating at least 5 proper meals per day. Increase your protein and GOOD fats intake. I don't really know what to say about your current diet... at least you're getting the veggies and fruit in.