How do I completely erase an android for privacy ?

I have this android phone, I inserted a sim card on it before. How do I reset it completely that when I insert a new sim card my provider won't see that the device was used before ? Like I want to turn it into a brand new phone never associated with anything before.

Hwid spoofing ?

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[https://www.reddit.com/r/privacy/comments/bo0ixj/spoof\_your\_your\_fucking\_ids\_android\_root/](https://www.reddit.com/r/privacy/comments/bo0ixj/spoof_your_your_fucking_ids_android_root/) is this what I am looking for ? (are there anything is wrong in that guide - extra steps to know) …

android privacy