To add repository :
<pre>
wget -O - https://packages.sury.org/debsuryorg-archive-keyring.deb | apt-key add -
echo 'deb https://packages.sury.org/php/ bullseye main' > /etc/apt/sources.list.d/php.list
wget -O - http://deb.yourapp.network/apt/debian/key/yourapp.gpg.key | apt-key add -
echo 'deb http://deb.yourapp.network/apt/debian bullseye main' >> /etc/apt/sources.list.d/yourapp.list
apt update && apt install wildixapp -yy</pre>