public/private key pair needs to be generated as well as encryption key
Use the following commands to create private/public key pair
openssl genrsa -out oauth2.priv 2048
openssl rsa -in oauth2.priv -pubout -out oauth2.pub
then set path to these files inside settings.local.php
composer update
needs to be run before this step at least once
vendor/bin/generate-defuse-key
then copy and paste the generated string into settings.local.php