You should root your device but after that you loose any warranty.
To see how to root your device check here.
For mail services you can use the encrypted Proton mail app with Proton VPN.
For anonymous browsing use Search engine DuckDuckGo. The only search engine that doesn't collect cookies. No trackers. You can also check the new duckduckgo.com search engine for .onion sites!
Google services collect your location all the time. You can check them out by monitoring your router. Custom ROMs supported without Google Store. You can also use Aptoide app store. You can controll your apps by closing unnecessary app-services. At last a root device can change the mac address and ΙΜΕΙ.