How do i get the license plate screws out on a 2010 Hyundai Santa Fe?

Those fixings are not a standard part of the car. They’re also very easily replaceable.

So if the screws won’t come out, get a broad-bladed flat screwdriver and wiggle the blade under the gap between the plate and the screw-head. Apply a bit of leverage and hold that screwdriver in place and then try unscrewing with your other screwdriver. 

If that fails, try grabbing the heads with a pair of pliers and turning them anticlockwise whilst pulling towards yourself. 

The next option would be to lever outwards as before and then use pliers or even nail pincers or the nail-remover on a claw hammer to just pull them out. Doing that will either leave slightly ragged holes in the plastic bumper cover, or will pull out some sacrificial nylon fixings. Ragged holes will be hidden when the plate goes back on: you may want to drill them out a size or so and then use suitable fixings; every car parts shop has loads of different ways to fasten number plates (or should do!) but even many household hardware fixings intended for fastening objects to thin materials like hardboard will be fine.

Many cars now come with moulded plastic cradles to fix standard-sized number plates, and even if they don’t there are many aftermarket sellers. The cradle gets fixed to the car and only replaced if it ever gets damaged, and the plates fix onto the cradle often using simple cheap self-tapping screws.

a] The type of vehicle is irrelevant.

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b] You probably need to hold the nuts on the back with a wrench. It's not exactly rocket science. 

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c] If the screws are mounted to steel nuts, they might be rusted and require a penetrating oil first.