My T20i has been acting weird

[Stevenseaball]

For the past week or two, I've noticed that my T20i is hesitant to start, has a rough idle and feel like it's coughing. One guy mentioned it could be the low pressure fuel pump, but he works as a boat mechanic, so he might be trying to scam me. Could he be right or is this a different problem

 

[JahBold]

Did you check the fuel filters or spark plugs yet? It could be the low-pressure fuel pump, but there are a few other things that can cause rough starts and idling too

 

[Stevenseaball]

Did you check the fuel filters or spark plugs yet? It could be the low-pressure fuel pump, but there are a few other things that can cause rough starts and idling too

That's the thing I wasn't sure where to start checking. I can check the filter and spark plugs, but how would I check the pump?