How to install php in Linux (Debian) on ChromeBook?

I am trying to install php in the Linux I set up, on my Chromebook,when activating developer mode. But, somehow it does seem to be working, despite a couple attempts on two different approaches:

1. Followed the link but I got this output:

   njtmendes@penguin:~$ sudo apt install -y php7.4 php7.4-cli php7.4-common
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
   E: Unable to locate package php7.4
   E: Couldn't find any package by glob 'php7.4'
   E: Couldn't find any package by regex 'php7.4'
   E: Unable to locate package php7.4-cli
   E: Couldn't find any package by glob 'php7.4-cli'
   E: Couldn't find any package by regex 'php7.4-cli'
   E: Unable to locate package php7.4-common
   E: Couldn't find any package by glob 'php7.4-common'
   E: Couldn't find any package by regex 'php7.4-common'
   njtmendes@penguin:~$ ^C
   njtmendes@penguin:~$ php -v
   -bash: php: command not found
   njtmendes@penguin:~$ ^C
   njtmendes@penguin:~$

2. I tried the solution above with the expectation of tweaking for Debiam but still doesn't work

   output:

   [6:16 pm, 28/04/2020] Nuno Da Elizabeth: njtmendes@penguin:~$ sudo add-apt-repository ppa:ondrej/php Co-installable PHP versions: PHP 5.6, PHP 7.x and most requested extensions are included. Only Supported Versions of PHP () for Supported Ubuntu Releases () are provided. Don't ask for end-of-life PHP versions or Ubuntu release, they won't be provided.
   Debian oldstable and stable packages are provided as well:
   You can get more information about the packages at
   BUGS&FEATURES: This PPA now has a issue tracker:
   CAVEATS:
   1. If you are using php-gearman, you need to add ppa:ondrej/pkg-gearman
   2. If you are using apache2, you are advised to add ppa:ondrej/apache2
   3. If you are using nginx, you are advise to add ppa:ondrej/nginx-mainline
      or ppa:ondrej/nginx
   PLEASE READ: If you like my work and want to give me a little motivation, please consider donating regularly:
   WARNING: add-apt-repository is broken with non-UTF-8 locales, see for workaround:
   # LC_ALL=C.UTF-8 add-apt-repository ppa:ondrej/php More info:
   Press [ENTER] to continue or ctrl-c to cancel adding it
   gpg: keybox '/tmp/tmpmbr9q9y5/pubring.gpg' created
   gpg: /tmp/tmpmbr9q9y5/trustdb.gpg: trustdb created
   gpg: key 4F4EA0AAE5267A6C: public key "Launchpad PPA for Ondřej Surý" imported
   gpg: Total number processed: 1
   gpg: imported: 1
   gpg: no valid OpenPGP data found.
   [6:17 pm, 28/04/2020] Helio: cool
   [6:18 pm, 28/04/2020] Helio: sudo apt-get update
   [6:18 pm, 28/04/2020] Nuno Da Elizabeth: njtmendes@penguin:~$ sudo apt-get update
   Hit:1 stable InRelease
   Ign:2 groovy InRelease
   Err:3 groovy Release 404 Not Found [IP: 2001:67c:1560:8008::15 80]
   Get:4 stretch InRelease [6,760 B]
   Hit:5 buster InRelease
   Hit:6 buster/updates InRelease
   Ign:7 buster InRelease
   Hit:8 buster Release
   Get:9 stretch/main amd64 Packages [136 kB]
   Reading package lists... Done
   E: The repository ' groovy Release' does not have a Release file.
   N: Updating from such a repository can't be done securely, and is therefore disabled by default.
   N: See apt-secure(8) manpage for repository creation and user configuration details.

   The output of the `apt update

   njtmendes@penguin:~$ sudo apt update
   Hit:1 stable InRelease
   Hit:2 buster InRelease
   Hit:3 buster/updates InRelease
   Ign:4 buster InRelease
   Hit:5 buster Release
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
   All packages are up to date.

It is quite frustrating not have been able to install PHP.

1 Answer

It appears you did not successfully add the PPA (additional repository) to your container, as instructed in your first link.

The instructions on that site indicate that you need to know which version of Debian you're running. The quickest way to do that on many Linux distributions is

cat /etc/os-release

Based on your ouptut from apt update I suspect you are running Buster (Debian 9)

To get the additional APT repository, follow these steps

sudo apt update
sudo apt install -y curl wget gnupg2 ca-certificates lsb-release apt-transport-https
wget
sudo apt-key add apt.gpg
echo "deb $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php7.list
sudo apt update

You will then be able to install the version of PHP you want

sudo apt -y install php7.4 php7.4-cli php7.4-common
php -v
PHP 7.4.6 (cli) (built: May 14 2020 10:03:28) ( NTS )
Copyright (c) The PHP Group
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