Why i dont have a GPS function on my 2013 chevy equinox LTZ .???

Did you order GPS? If not, go purchase a Garmin.

Or, use your cellphone, they have many universal mounts that attach to the windshield with a suction cup, really work well.

If your car does not have a navigation system it will not have GPS. Navigation is an option on most cars these days.

Might need to subscribe to onStar if vehicle is equipped with GPS as it should be since it is an LTZ with most major options included in that package.

Hold down the number 4 on your radio and the gps should come up on your infotainment system screen

will a tomtom work