How do I add and connect nodes?

Press N or / (or “Add node” on the left toolbar) to open the node menu, find the one you need and insert it. You can also drop or paste images and 3D models straight onto the canvas: each file creates its node.

To connect, drag from a node's output port (on the right) to a compatible input on another node (on the left). If you drop the wire on empty space, the menu opens filtered and the new node comes out already connected. If you move a node close to another with a free compatible port, they connect on their own. And “Quick connect”, on the node's toolbar, opens the menu with the compatible nodes: the one you pick is connected for you.