#First perform and apt update
sudo apt update && sudo apt upgrade -y
#Install dependencies
sudo apt install software-properties-common apt-transport-https -y
#Add the PPA
sudo add-apt-repository ppa:ondrej/php -y
#Now to install PHP 8.1 FPM and it's modules
sudo apt install php8.1-fpm php8.1-common php8.1-mysql php8.1-xml php8.1-xmlrpc php8.1-curl php8.1-gd php8.1-imagick php8.1-cli php8.1-dev php8.1-imap php8.1-mbstring php8.1-opcache php8.1-soap php8.1-zip php8.1-intl php8.1-bcmath