Currently, Videotron's 5G network uses the same band as the LTE network (1700Mhz and 2100 Mhz).
We cannot confirm if your specific device is compatible since devices bought in different markets may support different bands. This information should be available in your device's specifications. If the device is not compatible, a firmware update will not resolve the issue, as band compatibility is hardware and not software.
Should that be the case, it will be necessary to obtain a compatible device.