Question about weight gain?

Right now I weigh 75 pounds and am 5'4 (22yo). I'm underweight and I want to get to a BMI of 23-24

I just want to know what to expect, if i'll feel any different(i've heard you sweat more?) or if i'll need new clothes. So anyone who has gone from underweight to normal, what changes are there? I don't want the vague "you'll feel healthier", i just want to know if there are any other changes i must be aware of.

(I asked in askreddit but i feel like gaining weight is different for men and women)