I have an arris svg2482ac modem/router and i was gifted a device that requires i have a 2.4g wifi network as opposed to the 5G wifi network i currently set up through this modem/router, how do i add a 2.4 wifi network to this modem/router so i can connect this device?

Is there a specific app I should add to my phone to affect this?

How do I connect my phone to this modem/router - I guess which surfboard app do I need?

Can I please get basic advice or instructions to help here?

Thank you,

Simon.