Hi, I have problem with icons in gnome . i did turned on desktop icons NG extention but i have problem with “Adding” a icon to desktop like Pycharm or anything else i just can use trash and home icon i cant add anything to desktop and it is sooo bad if it is like this is will switch to Xfce again 
If you right-click on the desktop you will see “desktop icons setting” where you can set up DING as you require.
Also, In your Applications, you will find the Extensions manager. You can enable Applications Menu or Arc Menu which gives you something similar to ‘start menu’ ~ you can open apps quickly or other shortcuts you require.
If you want to add symlink (shortcut) to an app on the desktop - that’s a good question! I don’t know how, but I recommend you use the DOCK (dash-to-dock extension) which I think is better to organise apps you use often.
You can add symlinks to folders or files on the desktop though, just right-click the file/folder & choose “create link” then drag that symlink onto the desktop.
Gnome’s ethos is to have no icons on the desktop, which some people think is great & others (like me) think is terrible. What’s the point of a desktop if you cant put anything on it?! Anyway, thankfully there are lots of useful extensions you can use, so its not a problem.