Docker install ubuntu

Can someone explain how docker works.
I have an Odroid HC1 with Open Media Vault 6 installed.
Now I can open Portainer, but how do you create a container.
I’ve tried to install Ubuntu but can’t get it to work.
In terminal I also tried with docker pull ubuntu.
I then see the container in Open Media Vault, but it says exited.
How does this work ??

We can help with more specific questions but I would not expect anyone to explain how Docker works. You need to learn the basics before you start doing more complicated things.

Here is a tutorial that you can try:

One advice though: make sure your command running in the container is correct. Otherwise it will fail so your container will stop with an exit code.

Thanks for your message.
I still think it’s too complicated for me.
I’ve been working on it for a while but can’t get it to work.
There are too many settings that you need to get right to create a container.
Also, my English is not great.
I’m translating all the time, and I’m not getting anywhere.
Nevertheless, thank you for your message.
Gr from the Netherlands

I’ve looked at the explanation, but that’s way too much info for me.
Won’t go any further with it.
I’ve been trying to understand it for a few months now, but I still don’t understand it.
It may also be due to me that my English is not good.