some hospitals combine trauma + emergency general surgery. Some do ONLY trauma.
if your hospital combines - you'll see a lot of lap choleys, lap appies, maybe some colon/small bowel resections for acute abdomen (diverticulitis, perfed intestines) plus a few trauma cases.
If your hospital is just trauma: read up on trauma, from head to toe. figure out the indications for certain imaging, the indications for going to the OR, how to run a primary survey, what you are looking for when the patient rolls in. If you also round on the patients in the ICU, read up on vents, pressors, sepsis.