hai Aman,
As your BMI(
body mass index) is normal.
Initially don't go for any
protein supplements.
First eat protein nourished foods like Almond,cashew,channa,soyabean,peanut in your daily food intake.
Add jaggery,black gram,and dal prepared with ghee.
take diary product like milk,yogurt,cheese,butter etc. Add banana,arrowroot tuber vegetables.
take more water.
If you can eat meat take once in three days. add sea foods consistently.
This will nourish in a healthy way and gain weight.
protein supplement Endura mass advised for Athletes for sustain release of energy during their exercise. as your target of gaining weight didn't need that.
Normal being not advised to take endura mass.
Natural way to gain weight is advisable and safe.
thank you
hope i answered your query