Salesforce App Integeration - Classic Instructions Not Valid

Hello,

New to Ring Central. I'm trying to set up the integration for SF and RingCentral in the Admin Portal for RingCentral. The only instructions they provide are for SF Classic, but when following them, I find that the majority of items I need to select are not available (I am a SF admin).

I'm using https://support.ringcentral.com/s/article/9786?language=en_US and step 4, 5, 6, 7 aren't not accessible. Can someone please assist?