This is not a beginners job here. So many factors to consider: what year and model the car is?, are the intake gaskets leaking as well?, do u know how to bleed the system of air after you replace the pump?
To start, place a floor jack under the front of the oil pan. I like to use a small section of 2x4 to place in between the jack and the pan. Let the jack contact the pan just enough where it won't move around. Do not put a bunch of pressure on the pan!
Now, simply remove the engine mount, the belt and the pump. Depending on the set up, u can usually jack the engine up a few inches (no more) and be able to see all the bolts. They are 10 and 13mm. Use thread sealer on the 13mm ones and don't get crazy with silicone around the pump! Just clean the surface where the pump goes real good and you shouldn't have any problems. Be sure to bleed the air out of the system before any test drives... Good luck!