What's the most current reference for configuring Debian networking?

What's the most current reference documentation for configuring Debian networking?

I'm mired down in seeming old and outdated documentation. Here's what I've found so far:

• Lots of man pages. Some of them are new and some old, and because most are undated, it's hard to see what is what, in terms of age and what replaces what.

  Here is some of what I'm looking at (which I think are the most current):

  • Layer 2 - links
    interfaces(5) - configure physical and logical network interfaces, i.e. local hardware
    ifup(8).. - run scripts to bring interfaces up or down
    ip link(8) - other ways of bringing interfaces up or down
    iw(8) - wireless network interfaces
    networkctl(1) - query the status of network links as seen by systemd-networkd

  • Layer 3 - network
    hostname(7) - set/get my hostname
    hosts(5) - mostly obsolete - seems now only to be used by browsers to browse local files
    networks(5) - define locally known network name, alias and ip addresses (obsolete?)
    ip addr(8) - manage local IP addresses
    networkmanager(8), nmcli(1), networkmanager.conf(5), nm-applet(1), nm-connection-editor(1) - newer way to locally manage network??
    minissdpd(1) - daemon keeping track of UPnP devices up
    inetd(8) - daemon that listens on various TCP and UDP ports and spawns programs that can't or won't do it for themselves
    nmap(8) - Network exploration tool and security / port scanner

  • Layer 4+ - transport or above
    ss(8) - manage sockets ssh(1) - remote login program
    nfs(5) fstab format and options for the nfs file systems
    ...

• The Debian Administrator's Handbook - chapter 8.2. Configuring the Network - Undated, but it's now 2 major versions back, as Debian Buster is now up to version 10. Debian 8, or Jessie was released in April 2015, so this is now 5 years old.

• Debian Reference - Chapter 5. Network setup - but sadly says: "This chapter is getting outdated since this is based on Debian 7.0 (Wheezy) released in 2013.", so now 7 years old.

• Linux Network Administrators Guide - 3rd edition (2005), now 15 years old!

I'm hoping to better understand how the major network components fit together or replace each other on my system.

At the moment I'm trying to understand the ins and outs of using NetworkManager/nmcli, vs configuration files like /etc/network/interfaces, vs the ifup/ifdown and ip/ss commands, vs systemd.network (unit?) files.

I can see that ip, ss, and iw are the new command to learn, and am working on them. But I can also see that ifup and ifdown are not going away, because they run scripts that ip does not.

And I'm still confused about how exactly my system gets it's ip from the dhcp on my router.

(BTW, part of why I'm a little extra apprehensive about using old documentation. I already wasted a bunch of time learning iptables, only to later find that they were old and that I should be learning nftables.)

Thanks!