Go to [ctrl + t] terminal and run the command
--------Copy bellow command in terminal and enter---------
STEP:1 sudo su
STEP: 2
apt-get update && apt-get -y upgrade && apt-get install zip unzip
wget -q -O- https://debian.koha-community.org/koha/gpg.asc | sudo apt-key add - && sudo apt-get update && echo 'deb http://debian.koha-community.org/koha stable main' | sudo tee /etc/apt/sources.list.d/koha.list
wget https://koha.graviteclabs.online/wp-content/uploads/2022/01/koha-install.zip && unzip koha-install.zip
chmod 755 koha-install.sh && sh koha-install.sh
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