This looks like a man’s camp collar shirt in XXL. I have a similar shirt (smaller size), in short sleeves, from Old Navy. That’s not meant as a knock. You can be fashionable without paying Fendi prices, or even Nordstrom Rack or Off Fifth prices.
It’s hard to tell but it looks like it might actually fit in the shoulders, which it doesn’t if you’re just wearing a too large shirt that you like.
Whatever is going on the outfit looks great to me. I like the way the ‘pink’ in the skirt, which is unexpected, is in the shirt. And the tan/Brown sandals and bag are also following the shirt.:)