Hi ​@DMG 

Yes, the roaming data should be turned on in the phone settings, so you can use your mobile data in roaming (the International Data Roaming  Pay per use add on is required internationally for mobile data to work)

For calls and texts, it will work if you have the International Voice Roaming pay per use add on (under Mobile Services → Manage add ons)

If you turned off roaming by setting your network settings to Manual to Koodo, you should make sure it is switched back to Automatic