1) Buy a good Android phone supported by Lineage (check: https://download.lineageos.org/)
2) Install Lineage from https://download.lineageos.org
3) Install only free and open source anti-police state software from free and open source software repositories like fdroid: https://f-droid.org/en/
Recommended apps: https://prism-break.org/en/categories/android/
Use signal for calling: https://signal.org/
Don't use Line if you don#t have to: Line is a proprietary Korean software that tracks everything you do, like Facebook, Twitter, etc.
Cheers
TFF