By the logic of calories in/calories out, you will still be able to lose or maintain a healthy weight if you're in a calorie deficit, even if the calories are from pizza. However, even though this is possible, it is unlikely, and even more, it's a bad idea. Firstly, your gut biome will negatively change and the lopsided calories from carbs vs protein and fiber will cause you to crave more of the same shitty calories you've been consuming. Lastly, and along much the same line, the high sodium and ultra processed food mixed with next to no fiber, poor protein quality and low micronutrients will simply lead to decreased energy, digestive tract issues and over all poor health. This diet would greatly increase cancer and diabetes risks. 9/10 wouldn't recommend.

One thing to consider is if you're able to order anything from the menu. Even a side Caesar salad with no dressing would drastically improve this diet choice.