I'm assuming it's not an all keys lost situation. If the one working  key is a master key , you should be able to add a second key using the correct Toyota key that can turn ignition and using  using a manual method shown in video. I think the IM 508 should give you instructions to proceed with for adding a key if you have one working master key, as well as all keys lost. If the working key is not a Master key , you may need to erase all keys and start with the new unprogrammed (master) key as a all keys lost scenario, that I personally wouldn't want to try with my Autel IM508 unless I was parked near the Toyota Service department door. LMAO

https://www.youtube.com/watch?v=mEhLJibjiGc