Hi SerahM ,
It's definitely possible to do bulk imports. Depending on if this is something you'll want to do often, or if this is a one-off task, you should talk to your consultant to either:
1) Have them do it for you (if it's a one-off task)
OR
2) Have them set you up a good process for doing this frequently going forwards.
I've often seen this kind of import/update set up via Quick Insert Tables, but I caution against setting them up yourself as getting things wrong can be quite disruptive/require quite a bit of repair depending on exactly what you were doing and with which table.