INSTALL needs clarity

As I am trying to do a quite Simplistic deployment of libdvdcss off GIT I am finding MUCH confusion in the process and there is no real documentation.

Except the official one which reads:

Configuring libdvdcss
=====================

A typical way to configure libdvdcss is:

  ------------------------------------->  ./configure --prefix=/usr

See `./configure --help' for more information.

Question 1/4: what is this "./configure" file that you guys are referencing to?

In real life here is what happened on my system:

$ git clone https://code.videolan.org/videolan/libdvdcss.git 
Cloning into 'libdvdcss'...
remote: Enumerating objects: 2728, done.
remote: Counting objects: 100% (19/19), done.
remote: Compressing objects: 100% (13/13), done.
remote: Total 2728 (delta 5), reused 19 (delta 5), pack-reused 2709
Receiving objects: 100% (2728/2728), 793.03 KiB | 1.54 MiB/s, done.
Resolving deltas: 100% (1936/1936), done.
$ cd libdvdcss 
$ find . -name configure
$ tree
.
├── AUTHORS
├── configure.ac
├── COPYING
├── doc
│   └── doxygen.cfg.in
├── INSTALL
├── libdvdcss.spec.in
├── m4
│   └── attributes.m4
├── Makefile.am
├── msvc
│   ├── config.h
│   ├── csstest.dsp
│   ├── libdvdcss.dsp
│   ├── libdvdcss.vcxproj
│   └── workspace.dsw
├── NEWS
├── README.md
├── src
│   ├── common.h
│   ├── css.c
│   ├── css.h
│   ├── csstables.h
│   ├── device.c
│   ├── device.h
│   ├── dvdcss
│   │   ├── dvdcss.h
│   │   └── version.h.in
│   ├── error.c
│   ├── ioctl.c
│   ├── ioctl.h
│   ├── libdvdcss.c
│   ├── libdvdcss.h
│   └── libdvdcss.pc.in
└── test
    ├── csstest.c
    └── dvd_region.c

6 directories, 31 files
$ 

Question 2/4: same for the "autoreconf" reference:

If you got libdvdcss from its version control system, please bootstrap first:

  autoreconf -i  <-------------------------------------

Question 3/4: same for "make":

Building libdvdcss
==================

Once configured, run `make' to build libdvdcss.  <--------------------------------

If you have player keys, you need to put them in the file csskeys.h, before
configuring libdvdcss to enable the "key" method (the one from libcss).

But I still had to try some (silly) things. Of course, they all failed...

$ pwd
/home/luser/libdvdcss/
$ cd src
$ make
make: *** No targets specified and no makefile found.  Stop.
$ make .
make: Nothing to be done for '.'.
$ make ..
make: Nothing to be done for '..'.
$ make install
make: *** No rule to make target 'install'.  Stop.
$

Question 4/4: same for "make install"

Installing libdvdcss
====================

You can install libdvdcss by typing:

  make install

Thank you xo

$ uname -a
Linux luserbox 5.10.0-12-amd64 #1 SMP Debian 5.10.103-1 (2022-03-07) x86_64 GNU/Linux
$ cat /etc/os-release 
PRETTY_NAME="Debian GNU/Linux 11 (bullseye)"
NAME="Debian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
$