i have my phone to step 3 but can't proceed to step 4?

First part of Step 4 would be to Locate and view your connected device on your computer - Apple Support

don't see your device on your computer, learn what to do

Where are you getting stuck here? We'll try to help, but at this point things would likely be much easier if you were speaking to an Apple Support person over another phone connection......so they can guide you through step by step and answer any questions on the spot.

I have to catch a plane shortly, so I won't be able to check back for a time. Perhaps another user can pick up here and help out.