"Should" because the function of vaccines is to train our immune system to recognize the invading virus and kill it. If you haven't been exposed to it before, your body will not immediately recognize and kill it, and thus you get infected.

By training your body to recognize the proteins found on the spike, and the proteins found on the body of the virus, your body SHOULD then recognize the invaders when they come, and kill them off or at prevent them from taking over and killing you.

The difference in method between Novavax and the current vaccines is that the current ones train your immune system against the spike -- which can change. NVAX's vaccine trains your immune system to recognize PARTS of the spike and PARTS of the body of the vaccine -- and the body of the vaccine does NOT change even if the spike changes enough to evade the antibodies generated by the spike vaccines.

And, if you die the first time you get the virus, as so many do, how is your body supposed to be able to "figure it out" when you're in your grave?