This tutorial is for setting up a MikroTik router hap-ac2, to setup to the modem/router provided by my ISP, and use the latter as just a modem.

Text diagram of network

ISP Modem (public IP) - > MikroTik on ether1 (client dhcp set to grab public IP from ISP) - > ether2-ether5 will be bridge switch offering DHCP to my lan.