Not at all; it would actually be a starvation diet. Hell, even 1200 is the bare minimum for long term survival. The average (sedentary) woman needs 2000, average man needs 2500. They’ll need even more if they’re moving around. Not sure if you were looking for some advice too, but here it goes. In my experience, whenever I’ve needed to gain weight, I ate more nuts and seeds. They’re both calorie and nutrient dense and they could help you gain some weight a healthy way. You could also search calorie dense foods and eat some more of whatever comes up. I also really wouldn’t recommend starting calorie counting unless you’re deathly thin because it’ll only lead to obsession and make eating a chore. Hope this helps :)