my tahoe 2010 front small black skirt fell off is there any way i can fix it without a mechanic becuase mechanics are expensive and id like to do this fast
Yup, there is.
Buy a replacement (boneyard might save some bucks), drive the Tahoe up onto ramps (SAFELY; engine off, parking brake on), unscrew the remnants of the old one, and screw the new one back on.
A sheet of corrugated cardboard is the best thing ever to slid under the vehicle on. If you find some plastic screws/buttons/attachment pieces missing, you can pick up replacements at either parts stores or even big-box hardware stores.