I think my modem is getting outdated and I was wondering if this modem would work or overkill

Please refer to this list of Cox Certified Cable Modems and their compatible internet packages. 

https://www.cox.com/residential/support/cox-certified-cable-modems.html Thank you. 

ok thank you

I wouldn't suggest a modem/router combo. Separate modem and router is better. As for what to suggest, what speed do you pay for and what kind of wifi devices you have? Wifi 6/6e/7? Also, how big is your house? Do you need a mesh system? Last, what is your budget?