Pure drag and drop? no.
You need to search stuff, add to the tree, then manipulate on the visual editor, drag and drop is limited to some resources (mostly for textures).
I have seen something, maybe a plugin, that give some drag and drop capabilities but still have not seen the sources.
There will be a visual script editor on Godot 3, similar to Unreal blueprints.
If you know how to program on any language, from C to Lua, should be enough to understand GDScript (the main scripting language), Godot 3 may come with a version with C# support too.
If you don't know to program on any language, sadly there are no programming tutorials for gdscript but the closest language is Python, with plenty of online tutorials with interpreters (without installing anything).
For stuff that is too complex or special functions not included in the engine, you may need to add modules, currently on C++, but that may be more flexible in the near future.