DW HelpDesk – 2 Qs. How to add second language to the site and how to change the size of the logo or move it around?

 
If you want to translate the DW Helpdesk, you can use some the following plugins: 
 
https://wordpress.org/plugins/gtranslate/
https://wordpress.org/plugins/wp-multilang/
https://wordpress.org/plugins/translatepress-multilingual/
 

you can use the following code to change the logo size:

.navbar-brand>img {
width: …px;
height: …px;
}

To make the logo higher a bit, you can use the following code:

@media (min-width: 768px) {
.site-header .container {
position: relative;
}
.container>.navbar-header {
position: absolute;
top: -6px;
left: 0;
}
}