Is it possible to completely modify a stock ROM, so that the phone company and system apps can’t track me?

I bought a device with a Chinese ROM. Now a while ago just shifted to the global ROM of that device.
Now what I want to do is –

  1. I want to modify the whole ROM, so that the ROM owner/the phone company can’t track me and can’t get any data or anything out of my phone.

  2. Apart from the phone company I also don’t want other system apps like google and others to track me. So either I want to remove them, or want to remove their data collection capability.

  3. To be more specific – I actually want to modify or build my own ROM – that won’t track me, collect any data and I’ll be able to limit the data collection policy of whatever app I install.

If my whole expectation can come true then that’s fantastic but if a portion of what I want is possible still that’s great. So help me out.
And thanks in Advance.