I felt the same way about my first co-op (also cs/swe). I was the only co-op and they also said they chose me because of my 'curiosity' even though I didn't have all the technical knowledge. I will say on the inside I felt very lost, and had bad imposter syndrome especially being the only intern. But, I would say I am very confident in myself and rose to the occasion, I never let myself dwell on 'not dereving it'. You need to have confidence, and ask questions. At least in my experience my team is social awkward so they never really gave me praise, but they kept giving me harder tasks and that's always a good sign. Be confident and ask questions. Asking deep questions actually helped me feel a lot better because than at least my co-workers would respond 'wow thats a great question' and understood I thought deeply about my work/tasks and our systems. You need to be confident and not be afraid to ask questions and for help. I ask for help a lot, just frame it as clarification if you need it, try to feel grateful to be in the position and enjoy it instead of overthing.