Welcome to HealthcareMagic
WHEY PROTEIN 100% it is high protein drink, to build muscles they advised you to take. I believe you are vegetarian; you will not get that much protein from your diet. At least once a day you can take. Another two times you can have high protein foods like tofu(soy Paneer) Bengal gram, Black gram, Cow pea, Green gram, Lentils, Rajma, Soybean (Highest protein in this category but has moderate fat)
Cereals and Grains: Wheat germ
Nuts: like almonds, cashew nuts, groundnuts, sunflower seeds, water melon seeds etc., are also high in protein but contain high fat, Use them in small quantities to complement other sources of protein.
Milk and milk products: Cheese (high in fat), Paneer, Khoa, Thirattu pal - (From skimmed milk for low fat)
Excess of protein or any other nutrients do cause health problems. Since you are going for gym you will utilize protein whatever you will consume.
Daily protein intake should be a maximum of 1.4-1.8 g per kg body weight to enhance muscle protein synthesis or to make up for the loss of amino acid
oxidation during exercise. At least try to have 100 grams of protein per day.