I took my 98 accord to get inspected and it failed because of emissions test p1456. I was just curious if I could just do something about that myself or if I am going to have to put in the shop.

P1456--EVAP Emission Control System Leak Detected (Fuel Tank System)

The fuel tank isn't airtight. It could be a crack in the filler pipe, a loose/deteriorated hose, or even a bad gasket at the fuel gauge sender unit. Place the car on jack stands and check everything from the filter to the filler neck. You will likely be able to smell gas coming from somewhere.