With “drag and drop” you mean some kind of visual scripting, right?
Well, there is no visual script in Godot up to version 2.
Godot 3 has a visual script language called Visual Script (an original name, btw) but there is no way to turn from one to another because are not modes, are scripts “languages” (a converter should be possible to make may but does not make much sense).
Maybe you can try asking question about specific things that you see as difficult in the scripting language so documentation could be improved.