How to change the width of the site (to set the width to px) ?

Hello,

You can use CSS rules for that :

#container {
    max-width: 1020px;
}

Thanks!

Yay! Thank you Cchimps.

Hi! I’ve been doing these actions in style.css file and then upload it to the site, it is a bit uncomfortable. Is it possible to make these actions directly in the admin panel of the Site?

Try custom css plugin.

I have installed the plugin Simple Custom CSS. How to be written correctly?

Thanks, I understood!