[ossguy]

You could add this indirection layer with something like JMP instead.

With https://jmp.chat/ you don't need a SIM card at all - you just login to your phone number with an XMPP client (SMS/MMS) or SIP client (voice) and use it wherever you have an Internet connection. If you only want to use it at home, you can just use wifi and don't need to pay any cell carrier. But if you do want access to your number away from wifi, you can get a cheap data-only plan and use XMPP/SIP clients on your phone too. It's always up to you if you want to be tracked - you can turn off your phone('s modem) and use your number only over wifi whenever you like.

And it's easy to transfer your existing number into JMP - see https://jmp.chat/#existing for details.

[znpy]

No, that's not what I want. Stuff like JMP might not work in my country and would tie me to that particular provider.

I dream of a solution where I just put a SIM in and I am good to go (go as in "go away from the physical location of my sim card"). SMS will be forwarded to my email inbox and upon receiving a phone call it will be forwarded to the computer I am currently using via some protocol (SIP/webrtc?). Whether such computer is a mobile phone connected to the internet via a cellular modem or a laptop connected via some wifi that should not matter.

This should work with my current SIM card and with whatever other SIM card from any provider.

And BTW FYI: JMP does not work in my country. Please stop assuming everybody is from the US.