2 router and 2 broadband help

Hello people.

In my flat, theres currently a modem connecting to a broadband which the one im using now. Recently ive just purchased a new naked broadband(without homeline) that utilizes ADSL2+ and unfortunately, i have found out that that modem is an ADSL1 lol. To make long story short, i cant simply replace the ADSL1 modem with an ADSL2+ modem due to complicated reasons.

So my question is, is it possible to have 2 modems exist in the same flat with modem A connected to ISP A and modem B connected to ISP B? (I know that ADSL2+ broadband is compatible with ADSL1 modems but i dont want the speed to be capped)

p/s: my new broadband is still in the process, so i dont have it yet in my flat.

I'm not completely sure but I think you need 2 different lines to be able to do that. By different I mean not the usual one cable going out but really 2 cables going out of your house connecting to the ISP cables.

To be utilize both networks at the same thing, have fun buying advances switches and a pc to run pfSense with 3 dedicated network cards.