I feel someone has access to my phone / location because I am being tracked

what makes you think you are being tracked?

Do you use a passcode on your iPhone? Does anyone else know it? Does anyone know your Apple ID credentials?

Check your Apple ID device list to see where you're signed in - Apple Support

If you are concerned, change your phone passcode

Use a passcode with your iPhone, iPad, or iPod touch - Apple Support

change your Apple ID password

Change your Apple ID password - Apple Support

make sure you are using 2 factor authentication

Two-factor authentication for Apple ID - Apple Support

if you back up your phone to a computer, make sure that the backup is password protected

About encrypted backups on your iPhone, iPad, or iPod touch - Apple Support

An iPhone can't be tracked.