Will it affect my weight loss?

You can eat any food you would like and lose weight, as long as you stay within your calorie target.

You could live on butter and sugar and still lose weight if you are at a caloric deficit.

Will not affect it at all. I eat pizza once or twice a week. Never interfered with my losses or maintenance. Just be sure to get a reasonable calorie count for it and track it all.

And, because I think it's important, pizza can range from high to low calorie and can have good amounts of protein and fat. These are good things and it's not at all uncommon for folks to use it to hit our macros. Not unhealthy at all.

Weight loss is just about calories.

Most people care about health, too, so nutrition is also important.

Here's the thing: Pizza has this crazy-bad reputation, but it's just a combination of protein (mostly from meat/cheese, in most cases), fat (mostly from cheese/meat/oil), and carbs (mostly from flour, with a little from veggies). Nutrition involves getting reasonable amounts of protein, fat, and carbs, including veggies. Pizza can totally fit in there. Just think about portion size, and what you put on it (but keeping things you really like), and calculate calories accordingly.

Overall, it's:

Appropriate calories for weight management + balanced, well-rounded eating for nutrition + exercise for fitness = best odds of long term good health

. . . which is what most of us want, right? And, as others have said:

What we do on the majority of our days determines the majority of our outcomes.

Enjoy your pizza!