Hi, no problem! It's pretty simple actually, just pop your hood and locate the black rectangular box located in the right-rear portion (as observed when facing your engine once the hood is popped open) of the engine compartment. Looking straight down above the black box you will see 2 metal clips near the outside of the compartment and 1 metal clip hiding behind the box facing the motor. You don't need any tools, just pop all 3 clips with your fingers. Once popped-open, simply lift the upper housing of your air-filter box. You will immediately see your air filter resting in your housing, but sometimes the rubber gasket around the filter sticks to the top of the housing which might result in the filter becoming "unseated" from its normal resting position. When rested in the normal position, the air-filter should simply lift right out of the housing.
When getting a new filter, typically all you need to know is the year, make, and model of your vehicle and the parts store can re-direct you to the correct part number for a replacement filter. To install, simply follow the reverse of the above instructions. Important: make sure you have a perfect seal around your air filter housing by ensuring that the gasket of the filter is correctly "seated" in the proper resting position of the housing; you will know it is seated correctly when all 3 clips are "clipped-in" to position without too much effort; verify that the spacing between the upper and lower housing compartments is even all the way around the box, which should tell you that it is sealed and seated correctly.
Enjoy!