Drupal 8.x

Hi.

I'm quite new to Drupal, and are under the impression that nothing under the Drupal root folder (default /var/www/html) does not need to change when migrating from dev -> staging -> production. My reasoning is that I as a site developer can develop everything locally and deploy it to production, without making any changes along the way.

The contents created by the content creators, who log into the production site to create content, get stored in the database.

Is this a correct understanding of how Drupal works?

Hello There,

This error keeps coming up after I run the database update (which is fine), then get to the screen for going back to front page and.. get this:

Hello,

How can I change the position of  system messages? For example when I put the site under maintenance the message appears in the middle of the homepage but I prefer to see it on the top of the page. I checked block layout and there is nowhere a block about system messages. Any suggestions?

This happened before, and now happening again... I am logged in to my site as superuser.  The "Install New Module" button is not visible on my page.  Looking at the source code, I don't think it's there either.  I'm confused as to why.  I logged out, logged back in.  I cleared my cache... Still, the button is not visible.

I'm using Google Chrome... I also opened Firefox: the same thing happens there...

Below are two screenshots illustrating my issue. (I couldn't get the images to show up in this post...)

Hi,

first and foremost: I am not a Pro. I started to develop my own private site on my local laptop and by doing so came across different Ideas what I could ad. It is very likely that I know how something, but also that I miss here and there some basics (In general: Learning by doing).