Vanilla arm64 bullseye and vcgencmd / Install docs

[Ralph Aichinger <ra@pi.h5.or.at>]

Hi, I am very very happy with my RPi4 running Bullseye aarch64.
While the Raspberry Pi has right from the beginning been a very
pleasant device to work with, since the vanilla Debian port,
the solid USB boot, 64bit and enough RAM, to me it is more or
less indistinguishable from any other Debian box with amd64
or whatever. Yes, I know about the binary vc blob problem.

I've got 2 questions on this device:

Is there any way to either get "vcgencmd" from Raspberry Pi OS
or is there any other way to get the temperature of the board
as measured by internal sensors?

And: Is there any effort to get installing on RPi4 better documented,
eg to include the very comprehensive walkthrough in the RPi 
Forum as some kind of official installation documentation?

https://www.raspberrypi.org/forums/viewtopic.php?t=282839

I installed twice with that tutorial (with a few months
in between) and in my opinion this is the best description
on how to install on the RPi4, if there is something similar
on the Debian website, then I did not find it. Through its
availability and huge numbers sold, the RPi4 might become
a very popular Debian/arm64 platform IMHO.

I am somewhat hesitant to offer my help in compiling docs, 
as I am not a native speaker, but I'll gladly help out
in testing install documentation by checking it actually
works as described ;)

Thanks in advance, 
Ralph