Gaining

If you can afford it add boost vhc to your diet. Make sure you can handle it. I gained 7 pounds in a few days chugging a whole case in 3 days. But the taste isn't for everyone. Alternatively you can just eat sugary foods and increase calorie intake.

Eat a lot of the foods you like and the weight will follow. If you hold yourself to high calorie thresholds or try and eat a lot of fattening foods you don’t love gaining can start feeling like a chore, but if you keep it fun and enjoyable you’ll be able to maintain longer gains. That being said sodas are a good way to up your calorie intake if you don’t like heavy cream, even a slow gain is better than no gain at all

Only if you open it. You can store it anywhere as long as it's not too cold or too hot.

You can leave sweets and snacks nearby or always have a stocked snack drawer so you can have access to calories. Foods dense in fats/oils like nuts, avocados, butter also tend to have lots of calories.