Most TELUS devices sold since late 2017 were sold unlocked and do not need to be unlocked.
The best way to check if your device has been unlocked is to insert a SIM card from another carrier into your TELUS phone:
If you get the message
Invalid SIM
, you may need to unlock the device
If you do not have the
Invalid SIM
message but have no service or partial service, it may be an issue with the new carrier or the phone