Summer Internship Interview Help - Operations role

hi,

i am an undergrad student in the final year of my course. i have an uncoming interview for a Summer Internship Position in an Investment Bank's Operations division.

there will be a competency interview as well as a commercial interview.

how do i go about preparing for this? i can't seem to find enough information on operations and especially what 'commercial' means.

are there any services that offer mock interviews to help me prepare?