Bit doubtful VM would have totally removed a BT line but might perhaps (in the past) have re-purposed the BT socket/extensions for the phone line.
How did you receive the BT line in the past (from a pole overhead or underground cables)? Are there any traces of BT junction boxes outside your home where you can see the line comes to the building from the street?
If you don't actually have a line anymore, then your new provider would install one. This would be done via Openreach (rather than BT) as Openreach do the installations for other providers you might be considering. There may be a cost to install a new line. It might depend on which provider you choose as to how much it would cost.
If you have BT Full Fibre available in your area, and chose that, you would get a totally new fibre optic installation to your home. The old telephone cable would be redundant. Other providers would also most likely provide your landline via their router as VM do as that is part of a national rollout.
https://www.openreach.com/fibre-broadband/where-when-building-ultrafast-full-fibre-broadband
