It will not be possible to send/receive SMS messages outside of Japan as this service does not support international roaming.
If you are trying to get in touch with a contact, please contact them using a VOIP service instead ( Such as Whatsapp/Skype etc ) or via email.
If it’s a verification message you are requesting, we would suggest contacting the app/service provider to see if you can receive the message a different way, such as via email.