Can you post a link to your website, please?
The site you referring to is a non Joomla website.
In general use you can put Ninja Simple Icon Menu in any module position your template have.
If you want it on the left side you have to assign it to an available module position on the left.
If your template doesn't have a left module position then you can't assign Ninja Simple Icon Menu to it.
But, besides that, I think it needs more modifying if you want it placed on the outer side of the page.
Because usually Ninja Simple Icon Menu renders only in available positions and those available positions are usually rendered within a container that holds the initial content of the website.
As far as I understand, you want to place the module in the body tag of the main page, I think this is not possible (without modifying the code) and not intended to use it the way you want.
I'm not sure what you exactly mean, so if you could provide us a link to your page in question or a screenshot then this will be helpful to inspect things further.
I hope this helps.