Is there a way to see if someone is monitoring my phone/apps/location texting/phone calls or camera because they have access to the multiple phone account? And if so what is the solution short of opening a new account and moving my phone number?

Welcome to the Apple Support Communities.

iPhone cannot be compromised and there's nothing to worry about. However, if you are concerned about security, see: Apple Platform Security - Apple Support and Personal Safety User Guide - Apple Support.

If you are concerned about your Apple ID, see: If you think your Apple ID has been compromised - Apple Support.

For all third-party accounts, change the password. If you need any help, contact the manufacturer or service: Contact a third-party vendor - Apple Support.

To see what Apps can see your location, see: Turn Location Services and GPS on or off on your iPhone, iPad, or iPod touch - Apple Support.

Jack

Change your Apple ID password if you think someone knows it→Change your Apple ID password - Apple Support. And add 2 factor authentication so even if someone knows your password they can’t access your account→Two-factor authentication for Apple ID - Apple Support

Here’s more general information→If you think your Apple ID has been compromised - Apple Support

I’m having same issues. I live in TN and have got notifications saying someone in San Jose California is signing in on my account. My location is never right.

I do not longer have an I phone but someone's been using my accounts

I've tried that not getting anywhere as I use an android phone now