====MAIN METHOD======
Step 1. Check PHP version
php -v
-> output
PHP 7.0.33-0+deb9u8 (cli) (built: Jul 5 2020 06:34:50) ( NTS ) Copyright (c) 1997-2017 The PHP Group Zend Engine v3.0.0, Copyright (c) 1998-2017 Zend Technologies with Zend OPcache v7.0.33-0+deb9u8, Copyright (c) 1999-2017, by Zend Technologies
Step 2. Update System
apt update && apt upgrade
Maybe you will also need to reboot Debian.
Step 3. Configure PHP 7.4 Repository
sudo apt -y install lsb-release apt-transport-https ca-certificates sudo wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
Finally, use this command to add the repository
echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
Next, update system
apt update
Step 4. Install PHP 7.4 on Debian 9/10
sudo apt -y install lsb-release apt-transport-https ca-certificates sudo wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
Finally, use this command to add the repository
sudo apt install php7.4
Now check the PHP version using php -v command again and you should see the new version is installed as follow
Step 5. Install PHP modules
apt install -y php7.4-common php7.4-xml php7.4-mysql php7.4-pdo php7.4-phar php7.4-simplexml php7.4-curl php7.4-mbstring php7.4-imagick php7.4-zip php7.4-gd
Step 6. Disable PHP 7.0 module and Enable PHP 7.4 module
sudo a2dismod php7.0 sudo a2enmod php7.4 sudo systemctl restart apache2
Now, log in to WordPress again and the issue should be fixed. Your PHP installation is now up to date and you no longer see the “PHP Upgrade Required” error.
====ANOTHER METHOD======
Step 1: Update system
Ensure your system is updated:
sudo apt update sudo apt upgrade -y && sudo reboot
Step 2: Add SURY PHP PPA repository
Download and store PPA repository in a file on your Debian Server/Desktop. But first, download GPG key.
sudo apt -y install lsb-release apt-transport-https ca-certificates sudo wget -O /etc/apt/trusted.gpg.d/php.gpg https://packages.sury.org/php/apt.gpg
Then add the repository.
echo "deb https://packages.sury.org/php/ $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/php.list
Step 3: Install PHP 7.4 on Debian 10 / Debian 9
The last step is to Install PHP 7.4 on Debian 10 / Debian 9. Before installation, update system package list on added repositories.
sudo apt update
Then install PHP 7.4 on Debian 10 / Debian 9:
sudo apt -y install php7.4
Answer yes[just click enter] when prompted to complete installation of PHP 7.4 on Debian 10 / Debian 9 Linux system.
*** Install Additional Packages
sudo apt-get install php7.4-xxx
Example
sudo apt-get install php7.4-{bcmath,bz2,intl,gd,mbstring,mysql,zip}
PHP configurations related to Apache is stored in /etc/php/7.4/apache2/php.ini
*** Using PHP with Nginx:
sudo systemctl disable --now apache2 sudo apt-get install nginx php7.4-fpm
after that choose this from VESTA CP
Main Article: