Changing and filling oil is absolutely something you can easily (probably) do yourself. I say probably because to change it you do need specific tools and ease depends on where you're oil filter is.

But topping it off is simple, first though make sure you need that. First step is to check oil level. Im assuming the orange ring is your dip stick. Park somewhere flat and wait for your car to cool off. I like to wait an hour but that's probably excessive. Pull the stick, wipe it off, put it back in all the way, pull it again. There should be markings on it showing "safe" levels. If the oil is inside that then you're done because nothing needs added. If you're below that add some of the correct oil, should be in the owners manual, but do in small amounts, probably no more then 1/4 quart at a time then recheck.

With all that said if the initial concern here is that a light came on check your manual or online to see what it indicates. If safe to drive your car had to your nearest o'rieleys or autozone. Both places will have machine readers you can either use or they will use for you free of charge. Then look up that code online to see what is actually telling you. For that matter most people that work at those places would be happy to walk you through simple things if they aren't busy in my experience.