Im not an expert and i dont know all the ways grapheneos protects its users. But grapheneos is designed from the bottom up to remove google play services. Specifically MicroG. Which is a huge source of data export from your phone.

Linage os is not designed for high grade privacy and security. Its Barebones android, its often used by developers to write code for android apps and such. Lineageos is often used on hardware that is becoming out dated and can have security bugs and other problems because developers dont want to spend time fixing things on platforms that in EOL.

Now go read for yourself. Your asking some very basic questions here you could find out on the grapheneos website.

https://grapheneos.org/