I created a test topic, but the option does not appear to mark the answer as the best, what can it be?
Do you mean for the solved plugin? Only the post author and staff can mark a post as the solution.
לייק 1
How do I install this plugin?
See the first post here for instructions:
2 לייקים
Could the complete command be put? How to launch app.yml?
You need to SSH into your server, and edit your app.yml file (it’s just a text file)
It is located in /var/discourse/containers/.
לייק 1
I’m a little layman on this, if I pass SSH access, would you do it for me? Haha
I can’t, but if you post in marketplace someone might be able to help
לייק 1
Use this eating to access?
cd /var/discourse
/containers/app.yml
This is not working 
You are missing a command there.
cd /var/discourse
sudo nano containers/app.yml
2 לייקים
What do I do next?
Scroll to the bottom (using Page Dn), till you see the last - git clone ... command
Then add a new line, use spaces to ensure your - lines up (must be spaces, do not use tab) and paste the new git clone command
git clone https://github.com/discourse/discourse-solved.git
Then press CTRL + X, answer Y to save, press enter again (I think), then once at the console run
sudo ./launcher rebuild app
4 לייקים
This might help:
3 לייקים
I did what you taught me, the site went offline, is it normal?
Yes, it will go offline during a rebuild. It will be back up once the rebuild completes.
לייק 1
Would seem not, it seems your app.yml has an invalid character in it. On line 98. You can use nano to edit it again, and press CTRL + C to see what line your cursor is on. Find line 98 and take a screenshot of that area. If there is any sensitive info, such as passwords or email addresses, be sure to use an editing tool to blur them out.
לייק 1
I think what @cpradio meant was to go back into your app.yml file as per above
לייק 1
The site is still offline, will I miss it?