I have just purchased a 91 civic that has been sitting up for 4 years. It at first act like it wanted to start with the help of some starting fluid. After it would not start I drained the old gas out of the tank and replaced the fuel filter and it still will not start. I took the fuel line off the fuel pump and turned over the engine and no fuel was getting to the fuel filter. I guess it is the fuel pump. So could it be the fuel pump and where is it located and how difficult is it to change

Fuel pumps on Hondas are extremely reliable. My bet is there's an electrical-related problem. Perform tests, in Sections A and B, below:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563.html

Try jumping Terminals 5 and 7 on the main relay, if you don't hear the fuel pump run when you turn the ignition switch to ON (Position II). You should hear the fuel pump, inside the gas tank, run.

I replaced the fuel pump relay and the filter and fuel pump still getting no fuel to engine