Yes, as long as your current device is unlocked! Once you have activated a mobile plan and have received your new SIM card, simply insert the SIM card into your device to get connected. Refer to your device’s user guide for instructions on inserting the SIM card.
Note: Most devices purchased after December 1, 2017 may already be unlocked, subject to the manufacturer’s restrictions. If ever your phone is locked, you would need to contact your current provider.