Yep, thought that's what the bendie things would turn out to be
Take the big cap off. The little hole is just for when you may want to look at something very bright, sort of functions like a camera diaphragm, but nobody uses it anyway.
Lens size (114mm) is the diameter of the mirror in your scope. The larger diameter, the more photons it will capture, so a brighter image. Focal length (900mm) is like the length of a camera lens. the longer, the more telephoto effect but narrower view. Divide the Focal length by the diameter (900/114) and you have the overall "sensitivity" of the telescope: f7.9, just like a camera. (It's all just optics!)
They make different types of scopes that have various lens sizes (and cost) depending on what you want to look at; bright but big planets, less bright but medium size nebulas, dim and small remote galaxies.
Cheers,