Can I update my late 2011 Mac Pro to Mojave?

No your mac does not meet the hardware requirements for Mojave, namely a 'Metal' capable graphics card.

Read Section 1 of the compatibility table here,

Open Safari and click on this link, Firefox does not work.

How to upgrade to macOS Mojave - Apple Support

Not a 2011 model. If it could either be a Mid-2010 or Mid-2012 model, both of these could potentially be upgraded to Mojave if they have the recommended Metal-capable graphics card installed.

Ref: How to upgrade to macOS Mojave - Apple Support

Yeah High Sierra is as high as you can fly on that mac.

Their profile says MacBook Pro, that's what I am going on.

Good point! Let's see what they have to say ...

Thanks for verifying it is a MacBook Pro notebook and not the Mac Pro desktop. Sorry for my confusion. It looks like Eau Rouge has answered your question.