step1.

sudo apt-get update
sudo apt -y install software-properties-common
sudo add-apt-repository ppa:ondrej/nginx
sudo apt-get update

step2.
sudo apt -y install php7.4


A new version (/usr/lib/php/7.0/php.ini-production.cli) of configuration file /etc/php/7.0/cli/php.ini is available, but the version installed currently has been locally │
│ modified. │
│ │
│ What do you want to do about modified configuration file php.ini? │
│ │
│ install the package maintainer's version │
│ keep the local version currently installed │
│ show the differences between the versions │
│ show a side-by-side difference between the versions │
│ start a new shell to examine the situation │
│

https://kugancity.tistory.com/archive/20181209

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