Backup iPhone 6 to iMac

[Ski52]

Been trying to do this for the last 2 hours. Need to change my phone# and reset the phone due to unwanted porn/spam texts. I have blocked over 200 phone#'s in the last 2 weeks. Everywhere I go, it says to use iTunes. Well, I must be doing something wrong, cuz my iTunes comes up in a pink and blue screen with something about 'discover new music', with, it seems like no options to get to the sync/device/copy page. Tried to post a screenshot, but it says file too large - 586K?
Any help appreciated...

I won't use iCloud

 

[MightyGem]

Which version of MacOS are using on your Mac? If it's Catalina, iPhones are now synced through Finder.

Use the Finder to sync your iPhone, iPad, or iPod touch with your Mac - Apple Support

The Finder is one of the ways that you can sync your device with your Mac.

support.apple.com

 

[Ski52]

MightyGem - Sorry it has taken me so long to reply. I was going to attempt to get some vengeance on the scum that continues to hit me with 6 - 8 or more krap messages a day, I went onto TOR and found a couple of DoS routines that I could set two or three older computers, I have a few, in the garage and turn them loose on some 230 (and counting) websites/phone numbers. I went to the App Store today and found a copy of RoboKiller - free 7 days, then 40/year, had to re-enter the card data into the iPhone. Figured I'd give it a try. Less than 90 minutes later, I got a call from Capital 1, did I make 3 purchases from 3 vendors for the exact price???? So, I'm givin' up the fight. Gonna change my phone number, try to copy all my data off the phone, and reset it to blank factory. Got a new card commin' from Cap 1.
Anyone know of an easier way to do this, LMK pleeze...
Thanx
Ski