You will have to take it slow.

Lax engine took him 12 years to develop.

I am developing one of my own (as a hobby) and its been 5 years and counting.

Read the wiki, and use the forum to research specific topics.

I'm sorry but it does not seem that you will be able to accomplish this so easy and fast.

Perhaps, take a look at this engine (I was able to compile it with MinGW and CMake with no issues whatsoever):
https://urho3d.github.io/

It already has a GUI built-in if I am not mistaken.
And it also has physics and audio ready to go.

Also, take a look at this site:
https://www.gamefromscratch.com/

And check all the libraries and game engines available, perhaps you will find something more suitable.

If you want to stick to OGRE3D, all the power to you. I'm just trying to help.