Setting up home network, need some advice

Hey guys, so my fiancée and I just bought a house and are closing on the 14th, cox is the only provider in my area with higher speeds so we went with them

I’m going with 100mbps and did not want to rent their equipment. So I’m purchasing my own.

My question is, is a modem and router separate better in terms of performance and security than a modem router all I one.

Also I see I need a DOCSIS v3 modem, while browsing amazon I see some that have higher and lower channel bonding, like for instance one was 8x4 another 16x4, is higher better in this instance? I googled it but didn’t really understand it.

I do a lot of online gaming and school work for reference.

Thanks for any advice