How to install l2tp\ipsec on debian?

Question

Debian

Good afternoon GURU!
Help install L2TP \ IPSEC on PROXMOX. There are a lot of installation instructions on debian, but the main snag is that openswan is not installed.
---
Package openswan is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'openswan' has no installation candidate
--- That's why L2TP\IPSEC is chosen. OpenVPN is not considered yet, because. I don't want to add anything to my clients.

Answer 1

This decision is some kind of idiotic to raise something on the host, run debian virtual machines and raise them