As long as you use iOS (Apple) or Android (Google) services you will never have any kind of privacy.
First, using Gmail is not a good idea if you care about your privacy. Google is known to being reading email contents.
Second, you buy the device, not the OS. so both Apple and Google will try to profit from you using their OS.
Apple looks like is good for privacy, but I am afraid with iOS closed source there is no way to know. On iOS, app like TikTok can track the sh#t out of you even if you ask not to.
And Android is focused around Google, so using it means give up on privacy. However, you can install GrapheneOS (Android ROM), which is much more secure and privacy focused.