Student or Learner
Does it refer to the past or the present? "How could~ " is always confusing and seems dubious. Maybe it could be same as "How couldn't I have done that", referring to the past.
3)Show gratitude. When I got tenure, I took my research team to an amusement park for a week. One of the other professors asked, “How can you do that?” I said these people worked hard to help me get the best job in the world for life. How could I not do that?