iPhone spying

These articles might contain usable info for you:

Checklist: If you want to make sure no one else can see your location – Apple Support (AU)

and

Checklist: If you want to see if anyone else has access to your device or accounts - Apple Support

If you did not jailbreak it, it is not being "hacked".

If you did not share your location or iCloud account credentials with anyone, it is not being "tracked".