Click new type/input/interface/union/enum/scalar/directive
Type in the name of the node
Click enter
Select the node
Edit its name like a simple text input
To delete a node open the 3 dots menu on top of the active node and click Delete Node.
To duplicate node open the 3 dots menu on top of the active node and click Duplicate Node
Select a node
Click + button
Type in the name of the field type or select it.
Click it.
After that, the node field will be created with a default name (lowercase first letter type name). To change it, just select the created field and edit it like a simple text input.
Select a node
Click [!]
Select desired options
Select a node
Click the 3 dots menu on the desired field.
Click Delete
Select node
Click {} menu
Select desired interface
Select a node
Click @ menu
Select desired directive