How do i gain weight fast?

Exercise + protein: Resistance training plus healthy protein intake leads to muscle build up which adds healthy weight. It would be unethical to tell you how t gain unhealthy weight.

Not FAST.: 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 weight gain: almonds, cashews, pecans, sunflower seeds, flax seeds, walnuts, hummus, avocados, granola, trail mix, dried fruits, protein shakes & bars, lean meats