How to add or delete items from the desktop right click menu? From the main and the secondary drop down menu?
Have a looked at ~/Templates - all files there are shown in that submenu
I didn’t know that. Thanks! 
How to add/delete any item in the main drop down menu?
You cannot delete items - unless you want to compile Nautilus yourself
You can add items I think through using python-nautilus scripts I think.
OK, thanks!
I have no idea how to compile Nautilus.
When the Gnome/Nautilus devs remove support for handling the desktop, would Budgie stay with Nautilus 3.26 or try to patch it to get the same desktop handling as now?
Of course, I will test it. I have Ubuntu-Budgie 19.04. Going to read it. Thanks!