I want to gain weights, should i consider protein shakes?

Not necessarily: The key to gaining lean body mass is doing the work in the gym. From a dietary perspective, you need enough calories (but not too much), the appropriate vitamins and minerals, and enough protein to support your bodies attempt to build new muscle. Most people eating a typical western diet have no difficulty getting enough protein. They may need more fruits and veggies.

Eat healthy foods: that are high in calories. Eat 6 meals /day. Work on strength training to build large muscle groups. Work out w heavier weights w fewer repetitions. Sleep at least 8 to 9 hrs/night. Hydrate well w water. Foods to help w healthy weight gain: almonds, cashews, pecans, sunflower seeds, flax seeds, walnuts, hummus, avocados, granola, trail mix, dried fruits, protein shakes & bars, lean meats, poultry