Hello!
How can I move the logo and buttons to this place?

I tried through css but never found ((
I tried to edit the layout.tpl template and it gives the result, but I think that this is not correct

<div class="container-fluid" style="width:85%;">

How to do it right?

The easiest way to achieve it would be like you said make

<div class="container-fluid" style="width:85%;">

<div class="container" style="width:85%;">

But this can cause issues when you upgrade as your custom changes may be lost.

The css way is to give it

    max-width: 1140px;

Does this not work for you?

Thanks! Happened with css
I did not look there when I did it myself.
I got used to phpbb 3 all the time, but here everything is new =)