Supplement means when your diet is deficit in any Nutrients then we are providing that nutrient from other sources, that we called supplement. So everyone isn't required to supplement. So, for weight gain we suggest a high protein diet but if your diet is able to provide enough protein then you don't require any supplement. If your diet is deficit in protein then you should take a protein supplement.
Next Steps
first calculate your requirements. according to that you can plan your diet.
Health Tips
if you are on high protein your requirements should be around 1.2gm/ kg body weight no need to take too much protein. as it causes many other
kidney diseases.