use https://f-droid.org/packages/com.oasisfeng.island.fdroid/ (work profile) to isolate. and use a pay as you go number to register (rather than you commonly used one). do not grant any permission. set background restriction to strict. force stop it after every use. i think that would be enough
it might be a emulator. such as exagear. which only need a minimal linux environment to proot into. and all gui are done by wine