i give them layer! it’s just confusing because a lot of people say they still need the extra calcium and such
Layer is formulated to give an average layer enough calcium for good eggshells. Some birds need less, some need more. So I find it a pretty cheap investment to provide oyster shell for those that may need more.
If you feed layer and offer eggshells, and quality of shells is good, then what you're already doing is fine for your birds' needs.