Installing Rocketchat on a VPS on Ubuntu 19.04

Hello,
I am following this tutorial https://rocket.chat/docs/installation/docker-containers/ except that I’m stuck in step 6, this is what my VPS returns to me:
root@serveurs:~# docker-compose up -d
ERROR:
Can’t find a suitable configuration file in this directory or any
parent. Are you in the right directory?

    Supported filenames: docker-compose.yml, docker-compose.yaml

root@serveurs:~#

Make sure to move into what ever folder you copied the file into

Hi,
Thanks for your reply.
But i have the error bellow
root@serveurs:~# docker-compose up -d
ERROR:
Can’t find a suitable configuration file in this directory or any
parent. Are you in the right directory?

        Supported filenames: docker-compose.yml, docker-compose.yaml

root@serveurs:~#

In your tutorial once I finish with this file nano /var/www/rocket.chat/docker-compose.yml
I have to run this: docker-compose up -d
Here’s what he’s returning to me as a message
root @ servers: ~ # cd /var/www/rocket.chat/
root @ servers: /var/www/rocket.chat# docker-compose up -d
ERROR: Could not connect to Docker daemon. You might need to install Docker: