I would like to know how can I deactivate the responsive ability of the template.
The purpose of that I'm asking is for my website to be presented in the same way (menus, mainbody and sidebar on the right) on all devices (Desktops, laptos, tablets, mobiles etc).

Thank you.

You have to remove all the media queries.

meaning: All blocks that start with @media should be removed

I don't know what are media queries or blocks.
Can you give me a more detailed solution please (for starters)... :-)

Example:

Remove ALL code blocks that look like this (starting with @media only screen and (max-width: xxx ):
Always backup before performing such tasks.