I am 24 yrs M. Still not crossed 50 kg in my whole life, my current weight is 48 how do I achieve 58

Zheltrax

This app shows me 2500 surplus calories, since a beginner it's difficult to eat everytime also as a student

mar_sbar

In order to gain mass (muscle), part of it is being in a caloric surplus (the amount depends on what your ultimate physique goal is) and the other part is lifting with a hypertrophy-centered program. There are some good examples of programs online that you can look up. As a beginner, a 3 days a week full body workout would be great for you.

Diet-wise, it is helpful to start by slowly increasing your calories gradually so you won't shock your body and feel so uncomfortable. Start with an increase of 100 calories above maintenance, and then I crease that amount after a couple of weeks after your body has adjusted. The liquid calories route is also helpful as things like protein shakes, smoothies, and olive oil are easier to digest. Make sure you are getting 1.4 to 2 grams of protein per kilogram of body weight. Don't fear carbs, as those are necessary to fuel your workouts. Be sure to also cut out sugar and processed crap as much as possible.

I hope that was a helpful starting point. You can do this.