Following tutorials on what settings to configure on my device is useless if I don't learn what and how my device communicates with the network.

phones leak before those protections matter because phones are designed to stay connected at all costs.

If you don’t understand the network then phone hardening is cosmetic. You have to understand that first before we can fix the privacy of your phone.

You can't do anything if you have a data leak always connected in your pocket, you can REDUCE the leakage, as an article attached to this suggests.