I just received my circle lenses, can I soak them in the same solution they came in ?

No, you can't because it is saline water, not a solution for contact lens care, so you cannot soak your circle lenses in the same solution in which they were when you received your order.

You should take your contact lenses from their packaging bottle and soak them in multi-purpose contact lens solution overnight or at least 6 hours before you wear them for the first time.