I don't know about your situation with 2 ports on a cable modem - I have fios which doesn't use a modem, it just gives a WAN port. I don't think you can use your modem for 2 connections to the outside world. and 2 ports woukd make for a lousy switch. so id guess only 1 is usable.
As for router/switch/wifi APs, I use ubiquiti products. they can be a little intimidating if you're a novice. specifically I use egdemax 4 for a router, some unifi switches, 2 UAP-LRs for indoor wifi access points, and another (can't remember the model) that is waterproof for the backyard. I also use their security cameras and software. so I'm invested in their ecosystem.