Monica was not working so had to find a solution.
First step in the right direction was found: Github/nextcloud
Then figuring out how to do this: linuxhandbook.com
created a directory on the nas where i could build the image. Downloaded the files. modified the DockerFile from:
FROM php:8.0-apache
to
FROM php:8.0-apache-buster
after this you can run
docker build -t monica:apache-buster .
now you can use the apache-buster tag in your docker config to start the container.