Lens protector
Hello is lens protector worth it and can it crack your camera or the glass? Also does apple fix cracked cameras
iPhone 11, iOS 15
It depends on what the lens protector is. Apple onlysell things like the leather MagSafe case which should be thick enough to protect the lenses. Anything else presumably is removable for taking photos and you will have to look at the customer reviews for them.
Regarding the cost of repairing cameras or lenses at Apple, it is in the "Other Damage" category
https://support.apple.com/iphone/repair/service
You can see additional service information within the following article: