使用 apt install php7.4-cli 安裝
安裝 log:

root@test:/home/test# apt install php7.4-cli
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  php-common php7.4-common php7.4-json php7.4-opcache php7.4-readline
Suggested packages:
  php-pear
The following NEW packages will be installed:
  php-common php7.4-cli php7.4-common php7.4-json php7.4-opcache php7.4-readline
0 upgraded, 6 newly installed, 0 to remove and 71 not upgraded.
Need to get 2,643 kB of archives.
After this operation, 13.2 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://hk.archive.ubuntu.com/ubuntu focal/main amd64 php-common all 2:75 [11.9 kB]
Get:2 http://hk.archive.ubuntu.com/ubuntu focal-updates/main amd64 php7.4-common amd64 7.4.3-4ubuntu2.4 [979 kB]
Get:3 http://hk.archive.ubuntu.com/ubuntu focal-updates/main amd64 php7.4-json amd64 7.4.3-4ubuntu2.4 [19.2 kB]
Get:4 http://hk.archive.ubuntu.com/ubuntu focal-updates/main amd64 php7.4-opcache amd64 7.4.3-4ubuntu2.4 [198 kB]
Get:5 http://hk.archive.ubuntu.com/ubuntu focal-updates/main amd64 php7.4-readline amd64 7.4.3-4ubuntu2.4 [12.6 kB]
Get:6 http://hk.archive.ubuntu.com/ubuntu focal-updates/main amd64 php7.4-cli amd64 7.4.3-4ubuntu2.4 [1,422 kB]
Fetched 2,643 kB in 9s (303 kB/s)
Selecting previously unselected package php-common.
(Reading database ... 71351 files and directories currently installed.)
Preparing to unpack .../0-php-common_2%3a75_all.deb ...
Unpacking php-common (2:75) ...
Selecting previously unselected package php7.4-common.
Preparing to unpack .../1-php7.4-common_7.4.3-4ubuntu2.4_amd64.deb ...
Unpacking php7.4-common (7.4.3-4ubuntu2.4) ...
Selecting previously unselected package php7.4-json.
Preparing to unpack .../2-php7.4-json_7.4.3-4ubuntu2.4_amd64.deb ...
Unpacking php7.4-json (7.4.3-4ubuntu2.4) ...
Selecting previously unselected package php7.4-opcache.
Preparing to unpack .../3-php7.4-opcache_7.4.3-4ubuntu2.4_amd64.deb ...
Unpacking php7.4-opcache (7.4.3-4ubuntu2.4) ...
Selecting previously unselected package php7.4-readline.
Preparing to unpack .../4-php7.4-readline_7.4.3-4ubuntu2.4_amd64.deb ...
Unpacking php7.4-readline (7.4.3-4ubuntu2.4) ...
Selecting previously unselected package php7.4-cli.
Preparing to unpack .../5-php7.4-cli_7.4.3-4ubuntu2.4_amd64.deb ...
Unpacking php7.4-cli (7.4.3-4ubuntu2.4) ...
Setting up php-common (2:75) ...
Created symlink /etc/systemd/system/timers.target.wants/phpsessionclean.timer → /lib/systemd/system/phpsessionclean.timer.
Setting up php7.4-common (7.4.3-4ubuntu2.4) ...

Creating config file /etc/php/7.4/mods-available/calendar.ini with new version

Creating config file /etc/php/7.4/mods-available/ctype.ini with new version

Creating config file /etc/php/7.4/mods-available/exif.ini with new version

Creating config file /etc/php/7.4/mods-available/fileinfo.ini with new version

Creating config file /etc/php/7.4/mods-available/ffi.ini with new version

Creating config file /etc/php/7.4/mods-available/ftp.ini with new version

Creating config file /etc/php/7.4/mods-available/gettext.ini with new version

Creating config file /etc/php/7.4/mods-available/iconv.ini with new version

Creating config file /etc/php/7.4/mods-available/pdo.ini with new version

Creating config file /etc/php/7.4/mods-available/phar.ini with new version

Creating config file /etc/php/7.4/mods-available/posix.ini with new version

Creating config file /etc/php/7.4/mods-available/shmop.ini with new version

Creating config file /etc/php/7.4/mods-available/sockets.ini with new version

Creating config file /etc/php/7.4/mods-available/sysvmsg.ini with new version

Creating config file /etc/php/7.4/mods-available/sysvsem.ini with new version

Creating config file /etc/php/7.4/mods-available/sysvshm.ini with new version

Creating config file /etc/php/7.4/mods-available/tokenizer.ini with new version
Setting up php7.4-readline (7.4.3-4ubuntu2.4) ...

Creating config file /etc/php/7.4/mods-available/readline.ini with new version
Setting up php7.4-opcache (7.4.3-4ubuntu2.4) ...

Creating config file /etc/php/7.4/mods-available/opcache.ini with new version
Setting up php7.4-json (7.4.3-4ubuntu2.4) ...

Creating config file /etc/php/7.4/mods-available/json.ini with new version
Setting up php7.4-cli (7.4.3-4ubuntu2.4) ...
update-alternatives: using /usr/bin/php7.4 to provide /usr/bin/php (php) in auto mode
update-alternatives: using /usr/bin/phar7.4 to provide /usr/bin/phar (phar) in auto mode
update-alternatives: using /usr/bin/phar.phar7.4 to provide /usr/bin/phar.phar (phar.phar) in auto mode

Creating config file /etc/php/7.4/cli/php.ini with new version
Processing triggers for man-db (2.9.1-1) ...
Processing triggers for php7.4-cli (7.4.3-4ubuntu2.4) ...

打印測試

root@test:/home/test# echo '<?php echo "Hello ITHelp!";' | php
Hello ITHelp!