Have a look here: [https://github.com/paperless-ngx/paperless-ngx/blob/main/docker/compose/docker-compose.postgres.yml](paperless-ngx docker-compose.yml)
down under webserver:
you change data:/usr/src/paperless/data
to /path/to/where/you/wantorhave/your/files:/usr/src/paperless/data
. Same for the media path and you’re done. paperless now uses a folder on your machine instead of a volume.
If you want to be clean you will then also remove the volume declaration at the bottom of the file.
i think OP wants it to leave their current files alone. But Paperless doesn’t work like that, it deletes the originals and arranges the files its own way.