080208edf0baa - Netgear85 set up missing broadband connection

Hello, Earlier this week, I had to disconnect my Netgear85 wifi router (serial number 4yk175bmo72fc) for work so that I could have just Ethernet cable from my modem to my PC. My job says that I cannot have wifi on when working at home. When I tried to hook up the Netgear, I plugged the blue cable into the Ethernet hole and then into my internet modem, but there was an error. All lights on the router were green except the Broadband light. So I tried to put the blue cord into the Internet hole and there was still no broadband. Then, I moved the Netgear to another part of the house and tried to plug it into my cable modem that is hooked to my TV and got the same outcome (no broadband). What am I doing wrong? Can you help me set up my wifi router so that it would be easier for me to just turn it off when it is time for me to work from home on my PC using only Ethernet (no wifi)? Thanks! DC