How do I find names of components I don't know?
The Arduino webpage has a section about their Starter Kits, including pictures (and technical specs if you scroll down the page). Particularly, if you go to the Arduino store, there is a sub-menu for components - for example, for actuators (there are more categories to the left of the image).

There is a blog by Aaron Eiche, Arduino Starter Rundown, that if you scroll down, there is a chart that labels the main components.

There are several websites that have pages that identify components by image - an example is the uCHobby webpage Identifying Electronic Components, with pictorial menus of the main types of components.

In Google images, searching "arduino starter kit components" yields a considerable amount of labelled component charts.