Sure. A quick search of Amazon and I found this.
https://a.co/d/3eNs9hV
This being said, I'm sure it comes with all the panes of a screen protector, such as air bubbles and dust getting underneath it while you're trying to apply it. If somehow the screen is damaged by by the screen protector, it would not be covered under the warranty, because Apple does not recommend using one.
I've never felt the need, and I actually prefer the glossy finish of a MacBook versus what I consider the ugly matte finish of other computer monitors, but I can see if you're working in direct sunlight, or some situation like that how it would be annoying to have the glossy