Yes—on this kind of simple DIY or toy-style camera, the shutter speed and aperture are typically fixed, so every frame is exposed at essentially the same settings. You don’t change exposure shot to shot; instead, you choose film speed and shoot in lighting that suits those fixed settings.

That’s not how most traditional TLRs work—many have adjustable shutter speed and aperture—but inexpensive novelty or DIY models often behave more like a Holga, Brownie, or Instamatic: simple, limited control, and reliant on film’s exposure latitude.

In practice, you get usable results by:

• using film appropriate for the expected light
• shooting mostly in conditions that match the camera’s fixed exposure
• accepting that exposure may be approximate rather than precise

So your understanding is basically correct: with this camera, the whole roll is shot at one fixed exposure combination unless the camera includes some additional interchangeable aperture pieces or other exposure control not listed in the specs.