Get phone on I Tunes

To "come up" on itunes to do what exactly?

If connecting to a computer running iTunes, you just plug in one side of the charging cable to the iPhone and the other side to the computer.

iTunes should detect the iPhone and prompt you to trust it.

Then a small device icon will appear next to the media dropdown. Click on that to access the phone.

What version of iTunes do you have?

Also make sure the cable from the iPhone is connected directly to the computer.

Check different USB ports, and if possible check with different cables to be sure.

Restart your computer too.