how to change screw in wheel if its broken
if you mean lug nut,remove tire,remove brake caliper,remove rotor,spray with wd.40 or any lubricate to break rust.tap out from front with hammer,replace from back side,and reinstall all you removed.
Like TopShadeTree said. You need to remove the nut. Get a new one from your favorite parts dealer. Here is an image of the assembly: http://www.autopartsway.ca/PartList.cfm?Nissan/2012/Sentra/Base/2L-L4/allB/Driveline-and-Axles/Wheel-Bearings,-Seals,-and-Related-Components/Axle-Bearing-and-Hub-Assembly/pagenum1/tabS In your case, you only need the nut.
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