If you only have one key, you have no choice but to go to the dealer. They have to program it for you. You need 2 keys before you are allowed to program your own key (check owners manual). I bought my Liberty used and I only have one key and the dealer wants about $100 to supply and program a transponder key. For me it's not worth buying an Ebay key. Not like the old days

If you have two working keys already, then you will need to buy the "guts", to fill the shell you just bought, then you can program the transponder part and the remote control in a second step.